pgcat deb package

* Move connection checkin log messages to their own target

Under heavy load they can happen thousands of times per second, and
should generally be considered a nuisance at best. This marks the state
discard as an info rather than a warning, and moves all the messages
into their own log-target, so they can be filtered separately from the
more relevant warnings.

Signed-off-by: D.S. Ljungmark <spider@skuggor.se>

* Remove left-over env_logger dependencies

When moving to tracing-subscriber for logging, the env_logger
dependencies were left around, this cuts them out as dead code.

Signed-off-by: D.S. Ljungmark <spider@skuggor.se>

* Restore ability to filter log messages at runtime

This restores the RUST_LOG filters from env_logger but now with the
tracing subscriber setup. The filters are chained so commandline options
mark the default in case either option is set, which should be the path
of least confusion for users.  ( RUST_LOG setting level to debug, and
commandline to warning is an odd user case, and I don't know what a user
who does that is expecting. )

It also bumps the version number as a fix to see which versions have
which behaviour.

Signed-off-by: D.S. Ljungmark <spider@skuggor.se>

---------

Signed-off-by: D.S. Ljungmark <spider@skuggor.se>

.github/workflows/build-and-push.yaml

@@ -1,6 +1,11 @@
 name: Build and Push
 
-on: push
+on:
+  push:
+    branches:    
+      - main
+    tags:
+      - v*
 
 env:
   registry: ghcr.io
@@ -29,6 +34,7 @@ jobs:
           tags: |
             type=sha,prefix=,format=long
             type=schedule
+            type=ref,event=tag
             type=ref,event=branch
             type=ref,event=pr
             type=raw,value=latest,enable={{ is_default_branch }}

.github/workflows/publish-deb-package.yml

@@ -0,0 +1,48 @@
+name: pgcat package (deb)
+
+on:
+  workflow_dispatch:
+    inputs:
+      packageVersion:
+        default: "1.1.1"
+jobs:
+  build:
+    strategy:
+      max-parallel: 1
+      fail-fast: false # Let the other job finish, or they can lock each other out
+      matrix:
+        os: ["buildjet-4vcpu-ubuntu-2204", "buildjet-4vcpu-ubuntu-2204-arm"]
+
+    runs-on: ${{ matrix.os }}
+    steps:
+    - uses: actions/checkout@v3
+    - uses: actions-rs/toolchain@v1
+      with:
+        toolchain: stable
+    - name: Install dependencies
+      env:
+        DEBIAN_FRONTEND: noninteractive
+        TZ: Etc/UTC
+      run: |
+        curl -sLO https://github.com/deb-s3/deb-s3/releases/download/0.11.4/deb-s3-0.11.4.gem
+        sudo gem install deb-s3-0.11.4.gem
+        dpkg-deb --version
+    - name: Build and release package
+      env:
+        AWS_ACCESS_KEY_ID: ${{ vars.AWS_ACCESS_KEY_ID }}
+        AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
+        AWS_DEFAULT_REGION: ${{ vars.AWS_DEFAULT_REGION }}
+      run: |
+        if [[ $(arch) == "x86_64" ]]; then
+          export ARCH=amd64
+        else
+          export ARCH=arm64
+        fi
+
+        bash utilities/deb.sh ${{ inputs.packageVersion }}
+
+        deb-s3 upload \
+          --lock \
+          --bucket apt.postgresml.org \
+          pgcat-${{ inputs.packageVersion }}-ubuntu22.04-${ARCH}.deb \
+          --codename $(lsb_release -cs)

CONFIG.md

@@ -1,4 +1,4 @@
-# PgCat Configurations 
+# PgCat Configurations
 ## `general` Section
 
 ### host
@@ -116,10 +116,10 @@ If we should log client disconnections
 ### autoreload
 ```
 path: general.autoreload
-default: 15000
+default: 15000 # milliseconds
 ```
 
-When set to true, PgCat reloads configs if it detects a change in the config file.
+When set, PgCat automatically reloads its configurations at the specified interval (in milliseconds) if it detects changes in the configuration file. The default interval is 15000 milliseconds or 15 seconds.
 
 ### worker_threads
 ```
@@ -151,7 +151,13 @@ path: general.tcp_keepalives_interval
 default: 5
 ```
 
-Number of seconds between keepalive packets.
+### tcp_user_timeout
+```
+path: general.tcp_user_timeout
+default: 10000
+```
+A linux-only parameters that defines the amount of time in milliseconds that transmitted data may remain unacknowledged or buffered data may remain untransmitted (due to zero window size) before TCP will forcibly disconnect
+
 
 ### tls_certificate
 ```
@@ -224,7 +230,7 @@ default: "random"
 
 Load balancing mode
 `random` selects the server at random
-`loc` selects the server with the least outstanding busy conncetions
+`loc` selects the server with the least outstanding busy connections
 
 ### default_role
 ```

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pgcat"
-version = "1.0.2-alpha3"
+version = "1.1.1"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
@@ -8,7 +8,7 @@ edition = "2021"
 tokio = { version = "1", features = ["full"] }
 bytes = "1"
 md-5 = "0.10"
-bb8 = "0.8.0"
+bb8 = "0.8.1"
 async-trait = "0.1"
 rand = "0.8"
 chrono = "0.4"
@@ -19,10 +19,9 @@ serde_derive = "1"
 regex = "1"
 num_cpus = "1"
 once_cell = "1"
-sqlparser = {version = "0.33", features = ["visitor"] }
+sqlparser = {version = "0.34", features = ["visitor"] }
 log = "0.4"
 arc-swap = "1"
-env_logger = "0.10"
 parking_lot = "0.12.1"
 hmac = "0.12"
 sha2 = "0.10"
@@ -34,7 +33,7 @@ hyper = { version = "0.14", features = ["full"] }
 phf = { version = "0.11.1", features = ["macros"] }
 exitcode = "1.1.2"
 futures = "0.3"
-socket2 = { version = "0.5.3", features = ["all"] }
+socket2 = { version = "0.4.7", features = ["all"] }
 nix = "0.26.2"
 atomic_enum = "0.2.0"
 postgres-protocol = "0.6.5"
@@ -46,6 +45,9 @@ trust-dns-resolver = "0.22.0"
 tokio-test = "0.4.2"
 serde_json = "1"
 itertools = "0.10"
+clap = { version = "4.3.1", features = ["derive", "env"] }
+tracing = "0.1.37"
+tracing-subscriber = { version = "0.3.17", features = ["json", "env-filter", "std"]}
 
 [target.'cfg(not(target_env = "msvc"))'.dependencies]
 jemallocator = "0.5.0"

control

@@ -0,0 +1,9 @@
+Package: pgcat
+Version: ${PACKAGE_VERSION}
+Section: database
+Priority: optional
+Architecture: ${ARCH}
+Maintainer: PostgresML <team@postgresml.org>
+Homepage: https://postgresml.org
+Description: PgCat - NextGen PostgreSQL Pooler
+ PostgreSQL pooler and proxy (like PgBouncer) with support for sharding, load balancing, failover and mirroring.

dev/Dockerfile

@@ -1,4 +1,4 @@
-FROM rust:bullseye
+FROM rust:1.70-bullseye
 
 # Dependencies
 RUN apt-get update -y \

pgcat.toml

@@ -60,6 +60,12 @@ tcp_keepalives_count = 5
 # Number of seconds between keepalive packets.
 tcp_keepalives_interval = 5
 
+# Handle prepared statements.
+prepared_statements = true
+
+# Prepared statements server cache size.
+prepared_statements_cache_size = 500
+
 # Path to TLS Certificate file to use for TLS connections
 # tls_certificate = ".circleci/server.cert"
 # Path to TLS private key file to use for TLS connections
@@ -264,7 +270,7 @@ username = "sharding_user"
 # if `server_password` is not set.
 password = "sharding_user"
 
-pool_mode = "session"
+pool_mode = "transaction"
 
 # PostgreSQL username used to connect to the server.
 # server_username = "another_user"

src/admin.rs

@@ -1,4 +1,5 @@
 use crate::pool::BanReason;
+use crate::stats::pool::PoolStats;
 use bytes::{Buf, BufMut, BytesMut};
 use log::{error, info, trace};
 use nix::sys::signal::{self, Signal};
@@ -14,7 +15,7 @@ use crate::errors::Error;
 use crate::messages::*;
 use crate::pool::ClientServerMap;
 use crate::pool::{get_all_pools, get_pool};
-use crate::stats::{get_client_stats, get_pool_stats, get_server_stats, ClientState, ServerState};
+use crate::stats::{get_client_stats, get_server_stats, ClientState, ServerState};
 
 pub fn generate_server_info_for_admin() -> BytesMut {
     let mut server_info = BytesMut::new();
@@ -83,6 +84,10 @@ where
             shutdown(stream).await
         }
         "SHOW" => match query_parts[1].to_ascii_uppercase().as_str() {
+            "HELP" => {
+                trace!("SHOW HELP");
+                show_help(stream).await
+            }
             "BANS" => {
                 trace!("SHOW BANS");
                 show_bans(stream).await
@@ -254,39 +259,51 @@ async fn show_pools<T>(stream: &mut T) -> Result<(), Error>
 where
     T: tokio::io::AsyncWrite + std::marker::Unpin,
 {
-    let all_pool_stats = get_pool_stats();
+    let pool_lookup = PoolStats::construct_pool_lookup();
+    let mut res = BytesMut::new();
+    res.put(row_description(&PoolStats::generate_header()));
+    pool_lookup.iter().for_each(|(_identifier, pool_stats)| {
+        res.put(data_row(&pool_stats.generate_row()));
+    });
+    res.put(command_complete("SHOW"));
 
-    let columns = vec![
-        ("database", DataType::Text),
-        ("user", DataType::Text),
-        ("pool_mode", DataType::Text),
-        ("cl_idle", DataType::Numeric),
-        ("cl_active", DataType::Numeric),
-        ("cl_waiting", DataType::Numeric),
-        ("cl_cancel_req", DataType::Numeric),
-        ("sv_active", DataType::Numeric),
-        ("sv_idle", DataType::Numeric),
-        ("sv_used", DataType::Numeric),
-        ("sv_tested", DataType::Numeric),
-        ("sv_login", DataType::Numeric),
-        ("maxwait", DataType::Numeric),
-        ("maxwait_us", DataType::Numeric),
+    // ReadyForQuery
+    res.put_u8(b'Z');
+    res.put_i32(5);
+    res.put_u8(b'I');
+
+    write_all_half(stream, &res).await
+}
+
+/// Show all available options.
+async fn show_help<T>(stream: &mut T) -> Result<(), Error>
+where
+    T: tokio::io::AsyncWrite + std::marker::Unpin,
+{
+    let mut res = BytesMut::new();
+
+    let detail_msg = vec![
+        "",
+        "SHOW HELP|CONFIG|DATABASES|POOLS|CLIENTS|SERVERS|USERS|VERSION",
+        // "SHOW PEERS|PEER_POOLS", // missing PEERS|PEER_POOLS
+        // "SHOW FDS|SOCKETS|ACTIVE_SOCKETS|LISTS|MEM|STATE", // missing FDS|SOCKETS|ACTIVE_SOCKETS|MEM|STATE
+        "SHOW LISTS",
+        // "SHOW DNS_HOSTS|DNS_ZONES", // missing DNS_HOSTS|DNS_ZONES
+        "SHOW STATS", // missing STATS_TOTALS|STATS_AVERAGES|TOTALS
+        "SET key = arg",
+        "RELOAD",
+        "PAUSE [<db>, <user>]",
+        "RESUME [<db>, <user>]",
+        // "DISABLE <db>", // missing
+        // "ENABLE <db>", // missing
+        // "RECONNECT [<db>]", missing
+        // "KILL <db>",
+        // "SUSPEND",
+        "SHUTDOWN",
+        // "WAIT_CLOSE [<db>]", // missing
     ];
 
-    let mut res = BytesMut::new();
-    res.put(row_description(&columns));
-
-    for ((_user_pool, _pool), pool_stats) in all_pool_stats {
-        let mut row = vec![
-            pool_stats.database(),
-            pool_stats.user(),
-            pool_stats.pool_mode().to_string(),
-        ];
-        pool_stats.populate_row(&mut row);
-        pool_stats.clear_maxwait();
-        res.put(data_row(&row));
-    }
-
+    res.put(notify("Console usage", detail_msg.join("\n\t")));
     res.put(command_complete("SHOW"));
 
     // ReadyForQuery
@@ -334,17 +351,17 @@ where
                 let paused = pool.paused();
 
                 res.put(data_row(&vec![
-                    address.name(),                         // name
-                    address.host.to_string(),               // host
-                    address.port.to_string(),               // port
-                    database_name.to_string(),              // database
-                    pool_config.user.username.to_string(),  // force_user
-                    pool_config.user.pool_size.to_string(), // pool_size
-                    "0".to_string(),                        // min_pool_size
-                    "0".to_string(),                        // reserve_pool
-                    pool_config.pool_mode.to_string(),      // pool_mode
-                    pool_config.user.pool_size.to_string(), // max_connections
-                    pool_state.connections.to_string(),     // current_connections
+                    address.name(),                                          // name
+                    address.host.to_string(),                                // host
+                    address.port.to_string(),                                // port
+                    database_name.to_string(),                               // database
+                    pool_config.user.username.to_string(),                   // force_user
+                    pool_config.user.pool_size.to_string(),                  // pool_size
+                    pool_config.user.min_pool_size.unwrap_or(0).to_string(), // min_pool_size
+                    "0".to_string(),                                         // reserve_pool
+                    pool_config.pool_mode.to_string(),                       // pool_mode
+                    pool_config.user.pool_size.to_string(),                  // max_connections
+                    pool_state.connections.to_string(),                      // current_connections
                     match paused {
                         // paused
                         true => "1".to_string(),
@@ -725,6 +742,9 @@ where
         ("bytes_sent", DataType::Numeric),
         ("bytes_received", DataType::Numeric),
         ("age_seconds", DataType::Numeric),
+        ("prepare_cache_hit", DataType::Numeric),
+        ("prepare_cache_miss", DataType::Numeric),
+        ("prepare_cache_size", DataType::Numeric),
     ];
 
     let new_map = get_server_stats();
@@ -748,6 +768,18 @@ where
                 .duration_since(server.connect_time())
                 .as_secs()
                 .to_string(),
+            server
+                .prepared_hit_count
+                .load(Ordering::Relaxed)
+                .to_string(),
+            server
+                .prepared_miss_count
+                .load(Ordering::Relaxed)
+                .to_string(),
+            server
+                .prepared_cache_size
+                .load(Ordering::Relaxed)
+                .to_string(),
         ];
 
         res.put(data_row(&row));

src/client.rs

@@ -3,8 +3,9 @@ use crate::pool::BanReason;
 /// Handle clients by pretending to be a PostgreSQL server.
 use bytes::{Buf, BufMut, BytesMut};
 use log::{debug, error, info, trace, warn};
+use once_cell::sync::Lazy;
 use std::collections::HashMap;
-use std::sync::Arc;
+use std::sync::{atomic::AtomicUsize, Arc};
 use std::time::Instant;
 use tokio::io::{split, AsyncReadExt, BufReader, ReadHalf, WriteHalf};
 use tokio::net::TcpStream;
@@ -13,18 +14,25 @@ use tokio::sync::mpsc::Sender;
 
 use crate::admin::{generate_server_info_for_admin, handle_admin};
 use crate::auth_passthrough::refetch_auth_hash;
-use crate::config::{get_config, get_idle_client_in_transaction_timeout, Address, PoolMode};
+use crate::config::{
+    get_config, get_idle_client_in_transaction_timeout, get_prepared_statements, Address, PoolMode,
+};
 use crate::constants::*;
 use crate::messages::*;
 use crate::plugins::PluginOutput;
 use crate::pool::{get_pool, ClientServerMap, ConnectionPool};
 use crate::query_router::{Command, QueryRouter};
 use crate::server::Server;
-use crate::stats::{ClientStats, PoolStats, ServerStats};
+use crate::stats::{ClientStats, ServerStats};
 use crate::tls::Tls;
 
 use tokio_rustls::server::TlsStream;
 
+/// Incrementally count prepared statements
+/// to avoid random conflicts in places where the random number generator is weak.
+pub static PREPARED_STATEMENT_COUNTER: Lazy<Arc<AtomicUsize>> =
+    Lazy::new(|| Arc::new(AtomicUsize::new(0)));
+
 /// Type of connection received from client.
 enum ClientConnectionType {
     Startup,
@@ -93,6 +101,9 @@ pub struct Client<S, T> {
 
     /// Used to notify clients about an impending shutdown
     shutdown: Receiver<()>,
+
+    /// Prepared statements
+    prepared_statements: HashMap<String, Parse>,
 }
 
 /// Client entrypoint.
@@ -654,24 +665,12 @@ where
         ready_for_query(&mut write).await?;
 
         trace!("Startup OK");
-        let pool_stats = match get_pool(pool_name, username) {
-            Some(pool) => {
-                if !admin {
-                    pool.stats
-                } else {
-                    Arc::new(PoolStats::default())
-                }
-            }
-            None => Arc::new(PoolStats::default()),
-        };
-
         let stats = Arc::new(ClientStats::new(
             process_id,
             application_name,
             username,
             pool_name,
             tokio::time::Instant::now(),
-            pool_stats,
         ));
 
         Ok(Client {
@@ -694,6 +693,7 @@ where
             application_name: application_name.to_string(),
             shutdown,
             connected_to_server: false,
+            prepared_statements: HashMap::new(),
         })
     }
 
@@ -728,6 +728,7 @@ where
             application_name: String::from("undefined"),
             shutdown,
             connected_to_server: false,
+            prepared_statements: HashMap::new(),
         })
     }
 
@@ -769,6 +770,10 @@ where
         // Result returned by one of the plugins.
         let mut plugin_output = None;
 
+        // Prepared statement being executed
+        let mut prepared_statement = None;
+        let mut will_prepare = false;
+
         // Our custom protocol loop.
         // We expect the client to either start a transaction with regular queries
         // or issue commands for our sharding and server selection protocol.
@@ -778,13 +783,16 @@ where
                 self.transaction_mode
             );
 
+            // Should we rewrite prepared statements and bind messages?
+            let mut prepared_statements_enabled = get_prepared_statements();
+
             // Read a complete message from the client, which normally would be
             // either a `Q` (query) or `P` (prepare, extended protocol).
             // We can parse it here before grabbing a server from the pool,
             // in case the client is sending some custom protocol messages, e.g.
             // SET SHARDING KEY TO 'bigint';
 
-            let message = tokio::select! {
+            let mut message = tokio::select! {
                 _ = self.shutdown.recv() => {
                     if !self.admin {
                         error_response_terminal(
@@ -812,7 +820,21 @@ where
                 // allocate a connection, we wouldn't be able to send back an error message
                 // to the client so we buffer them and defer the decision to error out or not
                 // to when we get the S message
-                'D' | 'E' => {
+                'D' => {
+                    if prepared_statements_enabled {
+                        let name;
+                        (name, message) = self.rewrite_describe(message).await?;
+
+                        if let Some(name) = name {
+                            prepared_statement = Some(name);
+                        }
+                    }
+
+                    self.buffer.put(&message[..]);
+                    continue;
+                }
+
+                'E' => {
                     self.buffer.put(&message[..]);
                     continue;
                 }
@@ -842,6 +864,11 @@ where
                 }
 
                 'P' => {
+                    if prepared_statements_enabled {
+                        (prepared_statement, message) = self.rewrite_parse(message)?;
+                        will_prepare = true;
+                    }
+
                     self.buffer.put(&message[..]);
 
                     if query_router.query_parser_enabled() {
@@ -858,6 +885,10 @@ where
                 }
 
                 'B' => {
+                    if prepared_statements_enabled {
+                        (prepared_statement, message) = self.rewrite_bind(message).await?;
+                    }
+
                     self.buffer.put(&message[..]);
 
                     if query_router.query_parser_enabled() {
@@ -875,6 +906,19 @@ where
                     return Ok(());
                 }
 
+                // Close (F)
+                'C' => {
+                    if prepared_statements_enabled {
+                        let close: Close = (&message).try_into()?;
+
+                        if close.is_prepared_statement() && !close.anonymous() {
+                            self.prepared_statements.remove(&close.name);
+                            write_all_flush(&mut self.write, &close_complete()).await?;
+                            continue;
+                        }
+                    }
+                }
+
                 _ => (),
             }
 
@@ -1066,7 +1110,58 @@ where
             // If the client is in session mode, no more custom protocol
             // commands will be accepted.
             loop {
-                let message = match initial_message {
+                // Only check if we should rewrite prepared statements
+                // in session mode. In transaction mode, we check at the beginning of
+                // each transaction.
+                if !self.transaction_mode {
+                    prepared_statements_enabled = get_prepared_statements();
+                }
+
+                debug!("Prepared statement active: {:?}", prepared_statement);
+
+                // We are processing a prepared statement.
+                if let Some(ref name) = prepared_statement {
+                    debug!("Checking prepared statement is on server");
+                    // Get the prepared statement the server expects to see.
+                    let statement = match self.prepared_statements.get(name) {
+                        Some(statement) => {
+                            debug!("Prepared statement `{}` found in cache", name);
+                            statement
+                        }
+                        None => {
+                            return Err(Error::ClientError(format!(
+                                "prepared statement `{}` not found",
+                                name
+                            )))
+                        }
+                    };
+
+                    // Since it's already in the buffer, we don't need to prepare it on this server.
+                    if will_prepare {
+                        server.will_prepare(&statement.name);
+                        will_prepare = false;
+                    } else {
+                        // The statement is not prepared on the server, so we need to prepare it.
+                        if server.should_prepare(&statement.name) {
+                            match server.prepare(statement).await {
+                                Ok(_) => (),
+                                Err(err) => {
+                                    pool.ban(
+                                        &address,
+                                        BanReason::MessageSendFailed,
+                                        Some(&self.stats),
+                                    );
+                                    return Err(err);
+                                }
+                            }
+                        }
+                    }
+
+                    // Done processing the prepared statement.
+                    prepared_statement = None;
+                }
+
+                let mut message = match initial_message {
                     None => {
                         trace!("Waiting for message inside transaction or in session mode");
 
@@ -1165,7 +1260,7 @@ where
 
                             // Release server back to the pool if we are in transaction mode.
                             // If we are in session mode, we keep the server until the client disconnects.
-                            if self.transaction_mode {
+                            if self.transaction_mode && !server.in_copy_mode() {
                                 self.stats.idle();
 
                                 break;
@@ -1179,12 +1274,21 @@ where
                         self.stats.disconnect();
                         self.release();
 
+                        if prepared_statements_enabled {
+                            server.maintain_cache().await?;
+                        }
+
                         return Ok(());
                     }
 
                     // Parse
                     // The query with placeholders is here, e.g. `SELECT * FROM users WHERE email = $1 AND active = $2`.
                     'P' => {
+                        if prepared_statements_enabled {
+                            (prepared_statement, message) = self.rewrite_parse(message)?;
+                            will_prepare = true;
+                        }
+
                         if query_router.query_parser_enabled() {
                             if let Ok(ast) = QueryRouter::parse(&message) {
                                 if let Ok(output) = query_router.execute_plugins(&ast).await {
@@ -1199,17 +1303,45 @@ where
                     // Bind
                     // The placeholder's replacements are here, e.g. 'user@email.com' and 'true'
                     'B' => {
+                        if prepared_statements_enabled {
+                            (prepared_statement, message) = self.rewrite_bind(message).await?;
+                        }
+
                         self.buffer.put(&message[..]);
                     }
 
                     // Describe
                     // Command a client can issue to describe a previously prepared named statement.
                     'D' => {
+                        if prepared_statements_enabled {
+                            let name;
+                            (name, message) = self.rewrite_describe(message).await?;
+
+                            if let Some(name) = name {
+                                prepared_statement = Some(name);
+                            }
+                        }
+
                         self.buffer.put(&message[..]);
                     }
 
                     // Close the prepared statement.
                     'C' => {
+                        if prepared_statements_enabled {
+                            let close: Close = (&message).try_into()?;
+
+                            if close.is_prepared_statement() && !close.anonymous() {
+                                match self.prepared_statements.get(&close.name) {
+                                    Some(parse) => {
+                                        server.will_close(&parse.generated_name);
+                                    }
+
+                                    // A prepared statement slipped through? Not impossible, since we don't support PREPARE yet.
+                                    None => (),
+                                };
+                            }
+                        }
+
                         self.buffer.put(&message[..]);
                     }
 
@@ -1247,7 +1379,7 @@ where
                         let first_message_code = (*self.buffer.get(0).unwrap_or(&0)) as char;
 
                         // Almost certainly true
-                        if first_message_code == 'P' {
+                        if first_message_code == 'P' && !prepared_statements_enabled {
                             // Message layout
                             // P followed by 32 int followed by null-terminated statement name
                             // So message code should be in offset 0 of the buffer, first character
@@ -1278,7 +1410,7 @@ where
 
                             // Release server back to the pool if we are in transaction mode.
                             // If we are in session mode, we keep the server until the client disconnects.
-                            if self.transaction_mode {
+                            if self.transaction_mode && !server.in_copy_mode() {
                                 break;
                             }
                         }
@@ -1313,7 +1445,7 @@ where
                             .receive_server_message(server, &address, &pool, &self.stats.clone())
                             .await?;
 
-                        match write_all_half(&mut self.write, &response).await {
+                        match write_all_flush(&mut self.write, &response).await {
                             Ok(_) => (),
                             Err(err) => {
                                 server.mark_bad();
@@ -1343,7 +1475,13 @@ where
 
             // The server is no longer bound to us, we can't cancel it's queries anymore.
             debug!("Releasing server back into the pool");
+
             server.checkin_cleanup().await?;
+
+            if prepared_statements_enabled {
+                server.maintain_cache().await?;
+            }
+
             server.stats().idle();
             self.connected_to_server = false;
 
@@ -1375,6 +1513,107 @@ where
         }
     }
 
+    /// Rewrite Parse (F) message to set the prepared statement name to one we control.
+    /// Save it into the client cache.
+    fn rewrite_parse(&mut self, message: BytesMut) -> Result<(Option<String>, BytesMut), Error> {
+        let parse: Parse = (&message).try_into()?;
+
+        let name = parse.name.clone();
+
+        // Don't rewrite anonymous prepared statements
+        if parse.anonymous() {
+            debug!("Anonymous prepared statement");
+            return Ok((None, message));
+        }
+
+        let parse = parse.rename();
+
+        debug!(
+            "Renamed prepared statement `{}` to `{}` and saved to cache",
+            name, parse.name
+        );
+
+        self.prepared_statements.insert(name.clone(), parse.clone());
+
+        Ok((Some(name), parse.try_into()?))
+    }
+
+    /// Rewrite the Bind (F) message to use the prepared statement name
+    /// saved in the client cache.
+    async fn rewrite_bind(
+        &mut self,
+        message: BytesMut,
+    ) -> Result<(Option<String>, BytesMut), Error> {
+        let bind: Bind = (&message).try_into()?;
+        let name = bind.prepared_statement.clone();
+
+        if bind.anonymous() {
+            debug!("Anonymous bind message");
+            return Ok((None, message));
+        }
+
+        match self.prepared_statements.get(&name) {
+            Some(prepared_stmt) => {
+                let bind = bind.reassign(prepared_stmt);
+
+                debug!("Rewrote bind `{}` to `{}`", name, bind.prepared_statement);
+
+                Ok((Some(name), bind.try_into()?))
+            }
+            None => {
+                debug!("Got bind for unknown prepared statement {:?}", bind);
+
+                error_response(
+                    &mut self.write,
+                    &format!(
+                        "prepared statement \"{}\" does not exist",
+                        bind.prepared_statement
+                    ),
+                )
+                .await?;
+
+                Err(Error::ClientError(format!(
+                    "Prepared statement `{}` doesn't exist",
+                    name
+                )))
+            }
+        }
+    }
+
+    /// Rewrite the Describe (F) message to use the prepared statement name
+    /// saved in the client cache.
+    async fn rewrite_describe(
+        &mut self,
+        message: BytesMut,
+    ) -> Result<(Option<String>, BytesMut), Error> {
+        let describe: Describe = (&message).try_into()?;
+        let name = describe.statement_name.clone();
+
+        if describe.anonymous() {
+            debug!("Anonymous describe");
+            return Ok((None, message));
+        }
+
+        match self.prepared_statements.get(&name) {
+            Some(prepared_stmt) => {
+                let describe = describe.rename(&prepared_stmt.name);
+
+                debug!(
+                    "Rewrote describe `{}` to `{}`",
+                    name, describe.statement_name
+                );
+
+                Ok((Some(name), describe.try_into()?))
+            }
+
+            None => {
+                debug!("Got describe for unknown prepared statement {:?}", describe);
+
+                Ok((None, message))
+            }
+        }
+    }
+
     /// Release the server from the client: it can't cancel its queries anymore.
     pub fn release(&self) {
         let mut guard = self.client_server_map.lock();
@@ -1408,7 +1647,7 @@ where
                 .receive_server_message(server, address, pool, client_stats)
                 .await?;
 
-            match write_all_half(&mut self.write, &response).await {
+            match write_all_flush(&mut self.write, &response).await {
                 Ok(_) => (),
                 Err(err) => {
                     server.mark_bad();

src/cmd_args.rs

@@ -0,0 +1,36 @@
+use clap::{Parser, ValueEnum};
+use tracing::Level;
+
+/// PgCat: Nextgen PostgreSQL Pooler
+#[derive(Parser, Debug)]
+#[command(author, version, about, long_about = None)]
+pub struct Args {
+    #[arg(default_value_t = String::from("pgcat.toml"), env)]
+    pub config_file: String,
+
+    #[arg(short, long, default_value_t = tracing::Level::INFO, env)]
+    pub log_level: Level,
+
+    #[clap(short='F', long, value_enum, default_value_t=LogFormat::Text, env)]
+    pub log_format: LogFormat,
+
+    #[arg(
+        short,
+        long,
+        default_value_t = false,
+        env,
+        help = "disable colors in the log output"
+    )]
+    pub no_color: bool,
+}
+
+pub fn parse() -> Args {
+    return Args::parse();
+}
+
+#[derive(ValueEnum, Clone, Debug)]
+pub enum LogFormat {
+    Text,
+    Structured,
+    Debug,
+}

src/config.rs

@@ -261,6 +261,8 @@ pub struct General {
     pub tcp_keepalives_count: u32,
     #[serde(default = "General::default_tcp_keepalives_interval")]
     pub tcp_keepalives_interval: u64,
+    #[serde(default = "General::default_tcp_user_timeout")]
+    pub tcp_user_timeout: u64,
 
     #[serde(default)] // False
     pub log_client_connections: bool,
@@ -292,6 +294,9 @@ pub struct General {
     #[serde(default = "General::default_server_lifetime")]
     pub server_lifetime: u64,
 
+    #[serde(default = "General::default_server_round_robin")] // False
+    pub server_round_robin: bool,
+
     #[serde(default = "General::default_worker_threads")]
     pub worker_threads: usize,
 
@@ -317,6 +322,12 @@ pub struct General {
     pub auth_query: Option<String>,
     pub auth_query_user: Option<String>,
     pub auth_query_password: Option<String>,
+
+    #[serde(default)]
+    pub prepared_statements: bool,
+
+    #[serde(default = "General::default_prepared_statements_cache_size")]
+    pub prepared_statements_cache_size: usize,
 }
 
 impl General {
@@ -329,7 +340,7 @@ impl General {
     }
 
     pub fn default_server_lifetime() -> u64 {
-        1000 * 60 * 60 * 24 // 24 hours
+        1000 * 60 * 60 // 1 hour
     }
 
     pub fn default_connect_timeout() -> u64 {
@@ -351,8 +362,12 @@ impl General {
         5 // 5 seconds
     }
 
+    pub fn default_tcp_user_timeout() -> u64 {
+        10000 // 10000 milliseconds
+    }
+
     pub fn default_idle_timeout() -> u64 {
-        60000 // 10 minutes
+        600000 // 10 minutes
     }
 
     pub fn default_shutdown_timeout() -> u64 {
@@ -390,6 +405,14 @@ impl General {
     pub fn default_prometheus_exporter_port() -> i16 {
         9930
     }
+
+    pub fn default_server_round_robin() -> bool {
+        true
+    }
+
+    pub fn default_prepared_statements_cache_size() -> usize {
+        500
+    }
 }
 
 impl Default for General {
@@ -410,6 +433,7 @@ impl Default for General {
             tcp_keepalives_idle: Self::default_tcp_keepalives_idle(),
             tcp_keepalives_count: Self::default_tcp_keepalives_count(),
             tcp_keepalives_interval: Self::default_tcp_keepalives_interval(),
+            tcp_user_timeout: Self::default_tcp_user_timeout(),
             log_client_connections: false,
             log_client_disconnections: false,
             autoreload: None,
@@ -424,8 +448,11 @@ impl Default for General {
             auth_query: None,
             auth_query_user: None,
             auth_query_password: None,
-            server_lifetime: 1000 * 3600 * 24, // 24 hours,
+            server_lifetime: Self::default_server_lifetime(),
+            server_round_robin: Self::default_server_round_robin(),
             validate_config: true,
+            prepared_statements: false,
+            prepared_statements_cache_size: 500,
         }
     }
 }
@@ -487,10 +514,15 @@ pub struct Pool {
     #[serde(default)] // False
     pub primary_reads_enabled: bool,
 
+    /// Maximum time to allow for establishing a new server connection.
     pub connect_timeout: Option<u64>,
 
+    /// Close idle connections that have been opened for longer than this.
     pub idle_timeout: Option<u64>,
 
+    /// Close server connections that have been opened for longer than this.
+    /// Only applied to idle connections. If the connection is actively used for
+    /// longer than this period, the pool will not interrupt it.
     pub server_lifetime: Option<u64>,
 
     #[serde(default = "Pool::default_sharding_function")]
@@ -507,6 +539,9 @@ pub struct Pool {
     pub auth_query_user: Option<String>,
     pub auth_query_password: Option<String>,
 
+    #[serde(default = "Pool::default_cleanup_server_connections")]
+    pub cleanup_server_connections: bool,
+
     pub plugins: Option<Plugins>,
     pub shards: BTreeMap<String, Shard>,
     pub users: BTreeMap<String, User>,
@@ -548,6 +583,10 @@ impl Pool {
         ShardingFunction::PgBigintHash
     }
 
+    pub fn default_cleanup_server_connections() -> bool {
+        true
+    }
+
     pub fn validate(&mut self) -> Result<(), Error> {
         match self.default_role.as_ref() {
             "any" => (),
@@ -637,6 +676,7 @@ impl Default for Pool {
             auth_query_password: None,
             server_lifetime: None,
             plugins: None,
+            cleanup_server_connections: true,
         }
     }
 }
@@ -970,6 +1010,7 @@ impl Config {
             "Default max server lifetime: {}ms",
             self.general.server_lifetime
         );
+        info!("Sever round robin: {}", self.general.server_round_robin);
         match self.general.tls_certificate.clone() {
             Some(tls_certificate) => {
                 info!("TLS certificate: {}", tls_certificate);
@@ -993,6 +1034,13 @@ impl Config {
             "Server TLS certificate verification: {}",
             self.general.verify_server_certificate
         );
+        info!("Prepared statements: {}", self.general.prepared_statements);
+        if self.general.prepared_statements {
+            info!(
+                "Prepared statements server cache size: {}",
+                self.general.prepared_statements_cache_size
+            );
+        }
         info!(
             "Plugins: {}",
             match self.plugins {
@@ -1066,6 +1114,10 @@ impl Config {
                     None => "default".to_string(),
                 }
             );
+            info!(
+                "[pool: {}] Cleanup server connections: {}",
+                pool_name, pool_config.cleanup_server_connections
+            );
             info!(
                 "[pool: {}] Plugins: {}",
                 pool_name,
@@ -1208,9 +1260,15 @@ pub fn get_config() -> Config {
 }
 
 pub fn get_idle_client_in_transaction_timeout() -> u64 {
-    (*(*CONFIG.load()))
-        .general
-        .idle_client_in_transaction_timeout
+    CONFIG.load().general.idle_client_in_transaction_timeout
+}
+
+pub fn get_prepared_statements() -> bool {
+    CONFIG.load().general.prepared_statements
+}
+
+pub fn get_prepared_statements_cache_size() -> usize {
+    CONFIG.load().general.prepared_statements_cache_size
 }
 
 /// Parse the configuration file located at the path.

src/errors.rs

@@ -26,6 +26,7 @@ pub enum Error {
     AuthPassthroughError(String),
     UnsupportedStatement,
     QueryRouterParserError(String),
+    QueryRouterError(String),
 }
 
 #[derive(Clone, PartialEq, Debug)]
@@ -121,3 +122,9 @@ impl std::fmt::Display for Error {
         }
     }
 }
+
+impl From<std::ffi::NulError> for Error {
+    fn from(err: std::ffi::NulError) -> Self {
+        Error::QueryRouterError(err.to_string())
+    }
+}

src/lib.rs

@@ -1,13 +1,14 @@
 pub mod admin;
 pub mod auth_passthrough;
 pub mod client;
+pub mod cmd_args;
 pub mod config;
 pub mod constants;
 pub mod dns_cache;
 pub mod errors;
+pub mod logger;
 pub mod messages;
 pub mod mirrors;
-pub mod multi_logger;
 pub mod plugins;
 pub mod pool;
 pub mod prometheus;

src/logger.rs

@@ -0,0 +1,19 @@
+use crate::cmd_args::{Args, LogFormat};
+use tracing_subscriber;
+use tracing_subscriber::EnvFilter;
+
+pub fn init(args: &Args) {
+    // Iniitalize a default filter, and then override the builtin default "warning" with our
+    // commandline, (default: "info")
+    let filter = EnvFilter::from_default_env().add_directive(args.log_level.into());
+
+    let trace_sub = tracing_subscriber::fmt()
+        .with_env_filter(filter)
+        .with_ansi(!args.no_color);
+
+    match args.log_format {
+        LogFormat::Structured => trace_sub.json().init(),
+        LogFormat::Debug => trace_sub.pretty().init(),
+        _ => trace_sub.init(),
+    };
+}

src/main.rs

@@ -23,7 +23,6 @@ extern crate arc_swap;
 extern crate async_trait;
 extern crate bb8;
 extern crate bytes;
-extern crate env_logger;
 extern crate exitcode;
 extern crate log;
 extern crate md5;
@@ -61,15 +60,18 @@ use std::str::FromStr;
 use std::sync::Arc;
 use tokio::sync::broadcast;
 
+use pgcat::cmd_args;
 use pgcat::config::{get_config, reload_config, VERSION};
 use pgcat::dns_cache;
+use pgcat::logger;
 use pgcat::messages::configure_socket;
 use pgcat::pool::{ClientServerMap, ConnectionPool};
 use pgcat::prometheus::start_metric_server;
 use pgcat::stats::{Collector, Reporter, REPORTER};
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
-    pgcat::multi_logger::MultiLogger::init().unwrap();
+    let args = cmd_args::parse();
+    logger::init(&args);
 
     info!("Welcome to PgCat! Meow. (Version {})", VERSION);
 
@@ -78,20 +80,12 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         std::process::exit(exitcode::CONFIG);
     }
 
-    let args = std::env::args().collect::<Vec<String>>();
-
-    let config_file = if args.len() == 2 {
-        args[1].to_string()
-    } else {
-        String::from("pgcat.toml")
-    };
-
     // Create a transient runtime for loading the config for the first time.
     {
         let runtime = Builder::new_multi_thread().worker_threads(1).build()?;
 
         runtime.block_on(async {
-            match pgcat::config::parse(&config_file).await {
+            match pgcat::config::parse(args.config_file.as_str()).await {
                 Ok(_) => (),
                 Err(err) => {
                     error!("Config parse error: {:?}", err);

src/messages.rs

@@ -1,17 +1,21 @@
 /// Helper functions to send one-off protocol messages
 /// and handle TcpStream (TCP socket).
 use bytes::{Buf, BufMut, BytesMut};
-use log::error;
+use log::{debug, error};
 use md5::{Digest, Md5};
 use socket2::{SockRef, TcpKeepalive};
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
 use tokio::net::TcpStream;
 
+use crate::client::PREPARED_STATEMENT_COUNTER;
 use crate::config::get_config;
 use crate::errors::Error;
+
 use std::collections::HashMap;
+use std::ffi::CString;
 use std::io::{BufRead, Cursor};
 use std::mem;
+use std::sync::atomic::Ordering;
 use std::time::Duration;
 
 /// Postgres data type mappings
@@ -526,6 +530,33 @@ pub fn command_complete(command: &str) -> BytesMut {
     res
 }
 
+/// Create a notify message.
+pub fn notify(message: &str, details: String) -> BytesMut {
+    let mut notify_cmd = BytesMut::new();
+
+    notify_cmd.put_slice("SNOTICE\0".as_bytes());
+    notify_cmd.put_slice("C00000\0".as_bytes());
+    notify_cmd.put_slice(format!("M{}\0", message).as_bytes());
+    notify_cmd.put_slice(format!("D{}\0", details).as_bytes());
+
+    // this extra byte says that is the end of the package
+    notify_cmd.put_u8(0);
+
+    let mut res = BytesMut::new();
+    res.put_u8(b'N');
+    res.put_i32(notify_cmd.len() as i32 + 4);
+    res.put(notify_cmd);
+
+    res
+}
+
+pub fn flush() -> BytesMut {
+    let mut bytes = BytesMut::new();
+    bytes.put_u8(b'H');
+    bytes.put_i32(4);
+    bytes
+}
+
 /// Write all data in the buffer to the TcpStream.
 pub async fn write_all<S>(stream: &mut S, buf: BytesMut) -> Result<(), Error>
 where
@@ -658,6 +689,13 @@ pub fn configure_socket(stream: &TcpStream) {
     let sock_ref = SockRef::from(stream);
     let conf = get_config();
 
+    #[cfg(target_os = "linux")]
+    match sock_ref.set_tcp_user_timeout(Some(Duration::from_millis(conf.general.tcp_user_timeout)))
+    {
+        Ok(_) => (),
+        Err(err) => error!("Could not configure tcp_user_timeout for socket: {}", err),
+    }
+
     match sock_ref.set_keepalive(true) {
         Ok(_) => {
             match sock_ref.set_tcp_keepalive(
@@ -667,7 +705,7 @@ pub fn configure_socket(stream: &TcpStream) {
                     .with_time(Duration::from_secs(conf.general.tcp_keepalives_idle)),
             ) {
                 Ok(_) => (),
-                Err(err) => error!("Could not configure socket: {}", err),
+                Err(err) => error!("Could not configure tcp_keepalive for socket: {}", err),
             }
         }
         Err(err) => error!("Could not configure socket: {}", err),
@@ -689,3 +727,374 @@ impl BytesMutReader for Cursor<&BytesMut> {
         }
     }
 }
+
+/// Parse (F) message.
+/// See: <https://www.postgresql.org/docs/current/protocol-message-formats.html>
+#[derive(Clone, Debug)]
+pub struct Parse {
+    code: char,
+    #[allow(dead_code)]
+    len: i32,
+    pub name: String,
+    pub generated_name: String,
+    query: String,
+    num_params: i16,
+    param_types: Vec<i32>,
+}
+
+impl TryFrom<&BytesMut> for Parse {
+    type Error = Error;
+
+    fn try_from(buf: &BytesMut) -> Result<Parse, Error> {
+        let mut cursor = Cursor::new(buf);
+        let code = cursor.get_u8() as char;
+        let len = cursor.get_i32();
+        let name = cursor.read_string()?;
+        let query = cursor.read_string()?;
+        let num_params = cursor.get_i16();
+        let mut param_types = Vec::new();
+
+        for _ in 0..num_params {
+            param_types.push(cursor.get_i32());
+        }
+
+        Ok(Parse {
+            code,
+            len,
+            name,
+            generated_name: prepared_statement_name(),
+            query,
+            num_params,
+            param_types,
+        })
+    }
+}
+
+impl TryFrom<Parse> for BytesMut {
+    type Error = Error;
+
+    fn try_from(parse: Parse) -> Result<BytesMut, Error> {
+        let mut bytes = BytesMut::new();
+
+        let name_binding = CString::new(parse.name)?;
+        let name = name_binding.as_bytes_with_nul();
+
+        let query_binding = CString::new(parse.query)?;
+        let query = query_binding.as_bytes_with_nul();
+
+        // Recompute length of the message.
+        let len = 4 // self
+            + name.len()
+            + query.len()
+            + 2
+            + 4 * parse.num_params as usize;
+
+        bytes.put_u8(parse.code as u8);
+        bytes.put_i32(len as i32);
+        bytes.put_slice(name);
+        bytes.put_slice(query);
+        bytes.put_i16(parse.num_params);
+        for param in parse.param_types {
+            bytes.put_i32(param);
+        }
+
+        Ok(bytes)
+    }
+}
+
+impl TryFrom<&Parse> for BytesMut {
+    type Error = Error;
+
+    fn try_from(parse: &Parse) -> Result<BytesMut, Error> {
+        parse.clone().try_into()
+    }
+}
+
+impl Parse {
+    pub fn rename(mut self) -> Self {
+        self.name = self.generated_name.to_string();
+        self
+    }
+
+    pub fn anonymous(&self) -> bool {
+        self.name.is_empty()
+    }
+}
+
+/// Bind (B) message.
+/// See: <https://www.postgresql.org/docs/current/protocol-message-formats.html>
+#[derive(Clone, Debug)]
+pub struct Bind {
+    code: char,
+    #[allow(dead_code)]
+    len: i64,
+    portal: String,
+    pub prepared_statement: String,
+    num_param_format_codes: i16,
+    param_format_codes: Vec<i16>,
+    num_param_values: i16,
+    param_values: Vec<(i32, BytesMut)>,
+    num_result_column_format_codes: i16,
+    result_columns_format_codes: Vec<i16>,
+}
+
+impl TryFrom<&BytesMut> for Bind {
+    type Error = Error;
+
+    fn try_from(buf: &BytesMut) -> Result<Bind, Error> {
+        let mut cursor = Cursor::new(buf);
+        let code = cursor.get_u8() as char;
+        let len = cursor.get_i32();
+        let portal = cursor.read_string()?;
+        let prepared_statement = cursor.read_string()?;
+        let num_param_format_codes = cursor.get_i16();
+        let mut param_format_codes = Vec::new();
+
+        for _ in 0..num_param_format_codes {
+            param_format_codes.push(cursor.get_i16());
+        }
+
+        let num_param_values = cursor.get_i16();
+        let mut param_values = Vec::new();
+
+        for _ in 0..num_param_values {
+            let param_len = cursor.get_i32();
+            // There is special occasion when the parameter is NULL
+            // In that case, param length is defined as -1
+            // So if the passed parameter len is over 0
+            if param_len > 0 {
+                let mut param = BytesMut::with_capacity(param_len as usize);
+                param.resize(param_len as usize, b'0');
+                cursor.copy_to_slice(&mut param);
+                // we push and the length and the parameter into vector
+                param_values.push((param_len, param));
+            } else {
+                // otherwise we push a tuple with -1 and 0-len BytesMut
+                // which means that after encountering -1 postgres proceeds
+                // to processing another parameter
+                param_values.push((param_len, BytesMut::new()));
+            }
+        }
+
+        let num_result_column_format_codes = cursor.get_i16();
+        let mut result_columns_format_codes = Vec::new();
+
+        for _ in 0..num_result_column_format_codes {
+            result_columns_format_codes.push(cursor.get_i16());
+        }
+
+        Ok(Bind {
+            code,
+            len: len as i64,
+            portal,
+            prepared_statement,
+            num_param_format_codes,
+            param_format_codes,
+            num_param_values,
+            param_values,
+            num_result_column_format_codes,
+            result_columns_format_codes,
+        })
+    }
+}
+
+impl TryFrom<Bind> for BytesMut {
+    type Error = Error;
+
+    fn try_from(bind: Bind) -> Result<BytesMut, Error> {
+        let mut bytes = BytesMut::new();
+
+        let portal_binding = CString::new(bind.portal)?;
+        let portal = portal_binding.as_bytes_with_nul();
+
+        let prepared_statement_binding = CString::new(bind.prepared_statement)?;
+        let prepared_statement = prepared_statement_binding.as_bytes_with_nul();
+
+        let mut len = 4 // self
+            + portal.len()
+            + prepared_statement.len()
+            + 2 // num_param_format_codes
+            + 2 * bind.num_param_format_codes as usize // num_param_format_codes
+            + 2; // num_param_values
+
+        for (param_len, _) in &bind.param_values {
+            len += 4 + *param_len as usize;
+        }
+        len += 2; // num_result_column_format_codes
+        len += 2 * bind.num_result_column_format_codes as usize;
+
+        bytes.put_u8(bind.code as u8);
+        bytes.put_i32(len as i32);
+        bytes.put_slice(portal);
+        bytes.put_slice(prepared_statement);
+        bytes.put_i16(bind.num_param_format_codes);
+        for param_format_code in bind.param_format_codes {
+            bytes.put_i16(param_format_code);
+        }
+        bytes.put_i16(bind.num_param_values);
+        for (param_len, param) in bind.param_values {
+            bytes.put_i32(param_len);
+            bytes.put_slice(&param);
+        }
+        bytes.put_i16(bind.num_result_column_format_codes);
+        for result_column_format_code in bind.result_columns_format_codes {
+            bytes.put_i16(result_column_format_code);
+        }
+
+        Ok(bytes)
+    }
+}
+
+impl Bind {
+    pub fn reassign(mut self, parse: &Parse) -> Self {
+        self.prepared_statement = parse.name.clone();
+        self
+    }
+
+    pub fn anonymous(&self) -> bool {
+        self.prepared_statement.is_empty()
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct Describe {
+    code: char,
+
+    #[allow(dead_code)]
+    len: i32,
+    target: char,
+    pub statement_name: String,
+}
+
+impl TryFrom<&BytesMut> for Describe {
+    type Error = Error;
+
+    fn try_from(bytes: &BytesMut) -> Result<Describe, Error> {
+        let mut cursor = Cursor::new(bytes);
+        let code = cursor.get_u8() as char;
+        let len = cursor.get_i32();
+        let target = cursor.get_u8() as char;
+        let statement_name = cursor.read_string()?;
+
+        Ok(Describe {
+            code,
+            len,
+            target,
+            statement_name,
+        })
+    }
+}
+
+impl TryFrom<Describe> for BytesMut {
+    type Error = Error;
+
+    fn try_from(describe: Describe) -> Result<BytesMut, Error> {
+        let mut bytes = BytesMut::new();
+        let statement_name_binding = CString::new(describe.statement_name)?;
+        let statement_name = statement_name_binding.as_bytes_with_nul();
+        let len = 4 + 1 + statement_name.len();
+
+        bytes.put_u8(describe.code as u8);
+        bytes.put_i32(len as i32);
+        bytes.put_u8(describe.target as u8);
+        bytes.put_slice(statement_name);
+
+        Ok(bytes)
+    }
+}
+
+impl Describe {
+    pub fn rename(mut self, name: &str) -> Self {
+        self.statement_name = name.to_string();
+        self
+    }
+
+    pub fn anonymous(&self) -> bool {
+        self.statement_name.is_empty()
+    }
+}
+
+/// Close (F) message.
+/// See: <https://www.postgresql.org/docs/current/protocol-message-formats.html>
+#[derive(Clone, Debug)]
+pub struct Close {
+    code: char,
+    #[allow(dead_code)]
+    len: i32,
+    close_type: char,
+    pub name: String,
+}
+
+impl TryFrom<&BytesMut> for Close {
+    type Error = Error;
+
+    fn try_from(bytes: &BytesMut) -> Result<Close, Error> {
+        let mut cursor = Cursor::new(bytes);
+        let code = cursor.get_u8() as char;
+        let len = cursor.get_i32();
+        let close_type = cursor.get_u8() as char;
+        let name = cursor.read_string()?;
+
+        Ok(Close {
+            code,
+            len,
+            close_type,
+            name,
+        })
+    }
+}
+
+impl TryFrom<Close> for BytesMut {
+    type Error = Error;
+
+    fn try_from(close: Close) -> Result<BytesMut, Error> {
+        debug!("Close: {:?}", close);
+
+        let mut bytes = BytesMut::new();
+        let name_binding = CString::new(close.name)?;
+        let name = name_binding.as_bytes_with_nul();
+        let len = 4 + 1 + name.len();
+
+        bytes.put_u8(close.code as u8);
+        bytes.put_i32(len as i32);
+        bytes.put_u8(close.close_type as u8);
+        bytes.put_slice(name);
+
+        Ok(bytes)
+    }
+}
+
+impl Close {
+    pub fn new(name: &str) -> Close {
+        let name = name.to_string();
+
+        Close {
+            code: 'C',
+            len: 4 + 1 + name.len() as i32 + 1, // will be recalculated
+            close_type: 'S',
+            name,
+        }
+    }
+
+    pub fn is_prepared_statement(&self) -> bool {
+        self.close_type == 'S'
+    }
+
+    pub fn anonymous(&self) -> bool {
+        self.name.is_empty()
+    }
+}
+
+pub fn close_complete() -> BytesMut {
+    let mut bytes = BytesMut::new();
+    bytes.put_u8(b'3');
+    bytes.put_i32(4);
+    bytes
+}
+
+pub fn prepared_statement_name() -> String {
+    format!(
+        "P_{}",
+        PREPARED_STATEMENT_COUNTER.fetch_add(1, Ordering::SeqCst)
+    )
+}

src/mirrors.rs

@@ -7,8 +7,7 @@ use bytes::{Bytes, BytesMut};
 use parking_lot::RwLock;
 
 use crate::config::{get_config, Address, Role, User};
-use crate::pool::{ClientServerMap, PoolIdentifier, ServerPool};
-use crate::stats::PoolStats;
+use crate::pool::{ClientServerMap, ServerPool};
 use log::{error, info, trace, warn};
 use tokio::sync::mpsc::{channel, Receiver, Sender};
 
@@ -24,7 +23,7 @@ impl MirroredClient {
     async fn create_pool(&self) -> Pool<ServerPool> {
         let config = get_config();
         let default = std::time::Duration::from_millis(10_000).as_millis() as u64;
-        let (connection_timeout, idle_timeout, cfg) =
+        let (connection_timeout, idle_timeout, _cfg) =
             match config.pools.get(&self.address.pool_name) {
                 Some(cfg) => (
                     cfg.connect_timeout.unwrap_or(default),
@@ -34,16 +33,14 @@ impl MirroredClient {
                 None => (default, default, crate::config::Pool::default()),
             };
 
-        let identifier = PoolIdentifier::new(&self.database, &self.user.username);
-
         let manager = ServerPool::new(
             self.address.clone(),
             self.user.clone(),
             self.database.as_str(),
             ClientServerMap::default(),
-            Arc::new(PoolStats::new(identifier, cfg.clone())),
             Arc::new(RwLock::new(None)),
             None,
+            true,
         );
 
         Pool::builder()

src/multi_logger.rs

@@ -1,80 +0,0 @@
-use log::{Level, Log, Metadata, Record, SetLoggerError};
-
-// This is a special kind of logger that allows sending logs to different
-// targets depending on the log level.
-//
-// By default, if nothing is set, it acts as a regular env_log logger,
-// it sends everything to standard error.
-//
-// If the Env variable `STDOUT_LOG` is defined, it will be used for
-// configuring the standard out logger.
-//
-// The behavior is:
-//   - If it is an error, the message is written to standard error.
-//   - If it is not, and it matches the log level of the standard output logger (`STDOUT_LOG` env var), it will be send to standard output.
-//   - If the above is not true, it is sent to the stderr logger that will log it or not depending on the value
-//     of the RUST_LOG env var.
-//
-// So to summarize, if no `STDOUT_LOG` env var is present, the logger is the default logger. If `STDOUT_LOG` is set, everything
-// but errors, that matches the log level set in the `STDOUT_LOG` env var is sent to stdout. You can have also some esoteric configuration
-// where you set `RUST_LOG=debug` and `STDOUT_LOG=info`, in here, errors will go to stderr, warns and infos to stdout and debugs to stderr.
-//
-pub struct MultiLogger {
-    stderr_logger: env_logger::Logger,
-    stdout_logger: env_logger::Logger,
-}
-
-impl MultiLogger {
-    fn new() -> Self {
-        let stderr_logger = env_logger::builder().format_timestamp_micros().build();
-        let stdout_logger = env_logger::Builder::from_env("STDOUT_LOG")
-            .format_timestamp_micros()
-            .target(env_logger::Target::Stdout)
-            .build();
-
-        Self {
-            stderr_logger,
-            stdout_logger,
-        }
-    }
-
-    pub fn init() -> Result<(), SetLoggerError> {
-        let logger = Self::new();
-
-        log::set_max_level(logger.stderr_logger.filter());
-        log::set_boxed_logger(Box::new(logger))
-    }
-}
-
-impl Log for MultiLogger {
-    fn enabled(&self, metadata: &Metadata) -> bool {
-        self.stderr_logger.enabled(metadata) && self.stdout_logger.enabled(metadata)
-    }
-
-    fn log(&self, record: &Record) {
-        if record.level() == Level::Error {
-            self.stderr_logger.log(record);
-        } else {
-            if self.stdout_logger.matches(record) {
-                self.stdout_logger.log(record);
-            } else {
-                self.stderr_logger.log(record);
-            }
-        }
-    }
-
-    fn flush(&self) {
-        self.stderr_logger.flush();
-        self.stdout_logger.flush();
-    }
-}
-
-#[cfg(test)]
-mod test {
-    use super::*;
-
-    #[test]
-    fn test_init() {
-        MultiLogger::init().unwrap();
-    }
-}

src/pool.rs

@@ -1,6 +1,6 @@
 use arc_swap::ArcSwap;
 use async_trait::async_trait;
-use bb8::{ManageConnection, Pool, PooledConnection};
+use bb8::{ManageConnection, Pool, PooledConnection, QueueStrategy};
 use bytes::{BufMut, BytesMut};
 use chrono::naive::NaiveDateTime;
 use log::{debug, error, info, warn};
@@ -10,6 +10,7 @@ use rand::seq::SliceRandom;
 use rand::thread_rng;
 use regex::Regex;
 use std::collections::HashMap;
+use std::fmt::{Display, Formatter};
 use std::sync::{
     atomic::{AtomicBool, Ordering},
     Arc,
@@ -26,7 +27,7 @@ use crate::auth_passthrough::AuthPassthrough;
 use crate::plugins::prewarmer;
 use crate::server::Server;
 use crate::sharding::ShardingFunction;
-use crate::stats::{AddressStats, ClientStats, PoolStats, ServerStats};
+use crate::stats::{AddressStats, ClientStats, ServerStats};
 
 pub type ProcessId = i32;
 pub type SecretKey = i32;
@@ -76,6 +77,12 @@ impl PoolIdentifier {
     }
 }
 
+impl Display for PoolIdentifier {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}@{}", self.user, self.db)
+    }
+}
+
 impl From<&Address> for PoolIdentifier {
     fn from(address: &Address) -> PoolIdentifier {
         PoolIdentifier::new(&address.database, &address.username)
@@ -202,9 +209,6 @@ pub struct ConnectionPool {
     paused: Arc<AtomicBool>,
     paused_waiter: Arc<Notify>,
 
-    /// Statistics.
-    pub stats: Arc<PoolStats>,
-
     /// AuthInfo
     pub auth_hash: Arc<RwLock<Option<String>>>,
 }
@@ -254,10 +258,6 @@ impl ConnectionPool {
                     .clone()
                     .into_keys()
                     .collect::<Vec<String>>();
-                let pool_stats = Arc::new(PoolStats::new(identifier, pool_config.clone()));
-
-                // Allow the pool to be seen in statistics
-                pool_stats.register(pool_stats.clone());
 
                 // Sort by shard number to ensure consistency.
                 shard_ids.sort_by_key(|k| k.parse::<i64>().unwrap());
@@ -358,12 +358,12 @@ impl ConnectionPool {
                             user.clone(),
                             &shard.database,
                             client_server_map.clone(),
-                            pool_stats.clone(),
                             pool_auth_hash.clone(),
                             match pool_config.plugins {
                                 Some(ref plugins) => Some(plugins.clone()),
                                 None => config.plugins.clone(),
                             },
+                            pool_config.cleanup_server_connections,
                         );
 
                         let connect_timeout = match pool_config.connect_timeout {
@@ -389,6 +389,11 @@ impl ConnectionPool {
                             .min()
                             .unwrap();
 
+                        let queue_strategy = match config.general.server_round_robin {
+                            true => QueueStrategy::Fifo,
+                            false => QueueStrategy::Lifo,
+                        };
+
                         debug!(
                             "[pool: {}][user: {}] Pool reaper rate: {}ms",
                             pool_name, user.username, reaper_rate
@@ -401,6 +406,7 @@ impl ConnectionPool {
                             .idle_timeout(Some(std::time::Duration::from_millis(idle_timeout)))
                             .max_lifetime(Some(std::time::Duration::from_millis(server_lifetime)))
                             .reaper_rate(std::time::Duration::from_millis(reaper_rate))
+                            .queue_strategy(queue_strategy)
                             .test_on_check_out(false);
 
                         let pool = if config.general.validate_config {
@@ -428,7 +434,6 @@ impl ConnectionPool {
 
                 let pool = ConnectionPool {
                     databases: shards,
-                    stats: pool_stats,
                     addresses,
                     banlist: Arc::new(RwLock::new(banlist)),
                     config_hash: new_pool_hash_value,
@@ -609,6 +614,10 @@ impl ConnectionPool {
             });
         }
 
+        // Indicate we're waiting on a server connection from a pool.
+        let now = Instant::now();
+        client_stats.waiting();
+
         while !candidates.is_empty() {
             // Get the next candidate
             let address = match candidates.pop() {
@@ -627,10 +636,6 @@ impl ConnectionPool {
                 }
             }
 
-            // Indicate we're waiting on a server connection from a pool.
-            let now = Instant::now();
-            client_stats.waiting();
-
             // Check if we can connect
             let mut conn = match self.databases[address.shard][address.address_index]
                 .get()
@@ -668,7 +673,7 @@ impl ConnectionPool {
                     .stats()
                     .checkout_time(checkout_time, client_stats.application_name());
                 server.stats().active(client_stats.application_name());
-
+                client_stats.active();
                 return Ok((conn, address.clone()));
             }
 
@@ -676,11 +681,19 @@ impl ConnectionPool {
                 .run_health_check(address, server, now, client_stats)
                 .await
             {
+                let checkout_time: u64 = now.elapsed().as_micros() as u64;
+                client_stats.checkout_time(checkout_time);
+                server
+                    .stats()
+                    .checkout_time(checkout_time, client_stats.application_name());
+                server.stats().active(client_stats.application_name());
+                client_stats.active();
                 return Ok((conn, address.clone()));
             } else {
                 continue;
             }
         }
+        client_stats.idle();
         Err(Error::AllServersDown)
     }
 
@@ -914,13 +927,26 @@ impl ConnectionPool {
 
 /// Wrapper for the bb8 connection pool.
 pub struct ServerPool {
+    /// Server address.
     address: Address,
+
+    /// Server Postgres user.
     user: User,
+
+    /// Server database.
     database: String,
+
+    /// Client/server mapping.
     client_server_map: ClientServerMap,
-    stats: Arc<PoolStats>,
+
+    /// Server auth hash (for auth passthrough).
     auth_hash: Arc<RwLock<Option<String>>>,
+
+    /// Server plugins.
     plugins: Option<Plugins>,
+
+    /// Should we clean up dirty connections before putting them into the pool?
+    cleanup_connections: bool,
 }
 
 impl ServerPool {
@@ -929,18 +955,18 @@ impl ServerPool {
         user: User,
         database: &str,
         client_server_map: ClientServerMap,
-        stats: Arc<PoolStats>,
         auth_hash: Arc<RwLock<Option<String>>>,
         plugins: Option<Plugins>,
+        cleanup_connections: bool,
     ) -> ServerPool {
         ServerPool {
             address,
             user: user.clone(),
             database: database.to_string(),
             client_server_map,
-            stats,
             auth_hash,
             plugins,
+            cleanup_connections,
         }
     }
 }
@@ -956,7 +982,6 @@ impl ManageConnection for ServerPool {
 
         let stats = Arc::new(ServerStats::new(
             self.address.clone(),
-            self.stats.clone(),
             tokio::time::Instant::now(),
         ));
 
@@ -970,6 +995,7 @@ impl ManageConnection for ServerPool {
             self.client_server_map.clone(),
             stats.clone(),
             self.auth_hash.clone(),
+            self.cleanup_connections,
         )
         .await
         {

src/prometheus.rs

@@ -1,6 +1,6 @@
 use hyper::service::{make_service_fn, service_fn};
 use hyper::{Body, Method, Request, Response, Server, StatusCode};
-use log::{error, info, warn};
+use log::{debug, error, info};
 use phf::phf_map;
 use std::collections::HashMap;
 use std::fmt;
@@ -9,8 +9,9 @@ use std::sync::atomic::Ordering;
 use std::sync::Arc;
 
 use crate::config::Address;
-use crate::pool::get_all_pools;
-use crate::stats::{get_pool_stats, get_server_stats, ServerStats};
+use crate::pool::{get_all_pools, PoolIdentifier};
+use crate::stats::pool::PoolStats;
+use crate::stats::{get_server_stats, ServerStats};
 
 struct MetricHelpType {
     help: &'static str,
@@ -233,10 +234,10 @@ impl<Value: fmt::Display> PrometheusMetric<Value> {
         Self::from_name(&format!("stats_{}", name), value, labels)
     }
 
-    fn from_pool(pool: &(String, String), name: &str, value: u64) -> Option<PrometheusMetric<u64>> {
+    fn from_pool(pool_id: PoolIdentifier, name: &str, value: u64) -> Option<PrometheusMetric<u64>> {
         let mut labels = HashMap::new();
-        labels.insert("pool", pool.0.clone());
-        labels.insert("user", pool.1.clone());
+        labels.insert("pool", pool_id.db);
+        labels.insert("user", pool_id.user);
 
         Self::from_name(&format!("pools_{}", name), value, labels)
     }
@@ -274,7 +275,7 @@ fn push_address_stats(lines: &mut Vec<String>) {
                     {
                         lines.push(prometheus_metric.to_string());
                     } else {
-                        warn!("Metric {} not implemented for {}", key, address.name());
+                        debug!("Metric {} not implemented for {}", key, address.name());
                     }
                 }
             }
@@ -284,18 +285,15 @@ fn push_address_stats(lines: &mut Vec<String>) {
 
 // Adds relevant metrics shown in a SHOW POOLS admin command.
 fn push_pool_stats(lines: &mut Vec<String>) {
-    let pool_stats = get_pool_stats();
-    for (pool, stats) in pool_stats.iter() {
-        let stats = &**stats;
+    let pool_stats = PoolStats::construct_pool_lookup();
+    for (pool_id, stats) in pool_stats.iter() {
         for (name, value) in stats.clone() {
-            if let Some(prometheus_metric) = PrometheusMetric::<u64>::from_pool(pool, &name, value)
+            if let Some(prometheus_metric) =
+                PrometheusMetric::<u64>::from_pool(pool_id.clone(), &name, value)
             {
                 lines.push(prometheus_metric.to_string());
             } else {
-                warn!(
-                    "Metric {} not implemented for ({},{})",
-                    name, pool.0, pool.1
-                );
+                debug!("Metric {} not implemented for ({})", name, *pool_id);
             }
         }
     }
@@ -320,7 +318,7 @@ fn push_database_stats(lines: &mut Vec<String>) {
                     {
                         lines.push(prometheus_metric.to_string());
                     } else {
-                        warn!("Metric {} not implemented for {}", key, address.name());
+                        debug!("Metric {} not implemented for {}", key, address.name());
                     }
                 }
             }
@@ -366,7 +364,7 @@ fn push_server_stats(lines: &mut Vec<String>) {
                         {
                             lines.push(prometheus_metric.to_string());
                         } else {
-                            warn!("Metric {} not implemented for {}", key, address.name());
+                            debug!("Metric {} not implemented for {}", key, address.name());
                         }
                     }
                 }

src/query_router.rs

@@ -331,7 +331,7 @@ impl QueryRouter {
         Some((command, value))
     }
 
-    pub fn parse(message: &BytesMut) -> Result<Vec<sqlparser::ast::Statement>, Error> {
+    pub fn parse(message: &BytesMut) -> Result<Vec<Statement>, Error> {
         let mut message_cursor = Cursor::new(message);
 
         let code = message_cursor.get_u8() as char;
@@ -348,12 +348,13 @@ impl QueryRouter {
             // Parse (prepared statement)
             'P' => {
                 // Reads statement name
-                message_cursor.read_string().unwrap();
+                let _name = message_cursor.read_string().unwrap();
 
                 // Reads query string
                 let query = message_cursor.read_string().unwrap();
 
                 debug!("Prepared statement: '{}'", query);
+
                 query
             }
 

src/server.rs

@@ -5,7 +5,7 @@ use fallible_iterator::FallibleIterator;
 use log::{debug, error, info, trace, warn};
 use parking_lot::{Mutex, RwLock};
 use postgres_protocol::message;
-use std::collections::HashMap;
+use std::collections::{BTreeSet, HashMap};
 use std::io::Read;
 use std::net::IpAddr;
 use std::sync::Arc;
@@ -15,7 +15,7 @@ use tokio::net::TcpStream;
 use tokio_rustls::rustls::{OwnedTrustAnchor, RootCertStore};
 use tokio_rustls::{client::TlsStream, TlsConnector};
 
-use crate::config::{get_config, Address, User};
+use crate::config::{get_config, get_prepared_statements_cache_size, Address, User};
 use crate::constants::*;
 use crate::dns_cache::{AddrSet, CACHED_RESOLVER};
 use crate::errors::{Error, ServerIdentifier};
@@ -170,6 +170,9 @@ pub struct Server {
     /// Is there more data for the client to read.
     data_available: bool,
 
+    /// Is the server in copy-in or copy-out modes
+    in_copy_mode: bool,
+
     /// Is the server broken? We'll remote it from the pool if so.
     bad: bool,
 
@@ -188,13 +191,19 @@ pub struct Server {
     /// Application name using the server at the moment.
     application_name: String,
 
-    // Last time that a successful server send or response happened
+    /// Last time that a successful server send or response happened
     last_activity: SystemTime,
 
     mirror_manager: Option<MirroringManager>,
 
-    // Associated addresses used
+    /// Associated addresses used
     addr_set: Option<AddrSet>,
+
+    /// Should clean up dirty connections?
+    cleanup_connections: bool,
+
+    /// Prepared statements
+    prepared_statements: BTreeSet<String>,
 }
 
 impl Server {
@@ -207,6 +216,7 @@ impl Server {
         client_server_map: ClientServerMap,
         stats: Arc<ServerStats>,
         auth_hash: Arc<RwLock<Option<String>>>,
+        cleanup_connections: bool,
     ) -> Result<Server, Error> {
         let cached_resolver = CACHED_RESOLVER.load();
         let mut addr_set: Option<AddrSet> = None;
@@ -670,6 +680,7 @@ impl Server {
                         process_id,
                         secret_key,
                         in_transaction: false,
+                        in_copy_mode: false,
                         data_available: false,
                         bad: false,
                         cleanup_state: CleanupState::new(),
@@ -687,6 +698,8 @@ impl Server {
                                 address.mirrors.clone(),
                             )),
                         },
+                        cleanup_connections,
+                        prepared_statements: BTreeSet::new(),
                     };
 
                     server.set_name("pgcat").await?;
@@ -819,8 +832,19 @@ impl Server {
                     break;
                 }
 
+                // ErrorResponse
+                'E' => {
+                    if self.in_copy_mode {
+                        self.in_copy_mode = false;
+                    }
+                }
+
                 // CommandComplete
                 'C' => {
+                    if self.in_copy_mode {
+                        self.in_copy_mode = false;
+                    }
+
                     let mut command_tag = String::new();
                     match message.reader().read_to_string(&mut command_tag) {
                         Ok(_) => {
@@ -864,10 +888,14 @@ impl Server {
                 }
 
                 // CopyInResponse: copy is starting from client to server.
-                'G' => break,
+                'G' => {
+                    self.in_copy_mode = true;
+                    break;
+                }
 
                 // CopyOutResponse: copy is starting from the server to the client.
                 'H' => {
+                    self.in_copy_mode = true;
                     self.data_available = true;
                     break;
                 }
@@ -905,6 +933,119 @@ impl Server {
         Ok(bytes)
     }
 
+    /// Add the prepared statement to being tracked by this server.
+    /// The client is processing data that will create a prepared statement on this server.
+    pub fn will_prepare(&mut self, name: &str) {
+        debug!("Will prepare `{}`", name);
+
+        self.prepared_statements.insert(name.to_string());
+        self.stats.prepared_cache_add();
+    }
+
+    /// Check if we should prepare a statement on the server.
+    pub fn should_prepare(&self, name: &str) -> bool {
+        let should_prepare = !self.prepared_statements.contains(name);
+
+        debug!("Should prepare `{}`: {}", name, should_prepare);
+
+        if should_prepare {
+            self.stats.prepared_cache_miss();
+        } else {
+            self.stats.prepared_cache_hit();
+        }
+
+        should_prepare
+    }
+
+    /// Create a prepared statement on the server.
+    pub async fn prepare(&mut self, parse: &Parse) -> Result<(), Error> {
+        debug!("Preparing `{}`", parse.name);
+
+        let bytes: BytesMut = parse.try_into()?;
+        self.send(&bytes).await?;
+        self.send(&flush()).await?;
+
+        // Read and discard ParseComplete (B)
+        match read_message(&mut self.stream).await {
+            Ok(_) => (),
+            Err(err) => {
+                self.bad = true;
+                return Err(err);
+            }
+        }
+
+        self.prepared_statements.insert(parse.name.to_string());
+        self.stats.prepared_cache_add();
+
+        debug!("Prepared `{}`", parse.name);
+
+        Ok(())
+    }
+
+    /// Maintain adequate cache size on the server.
+    pub async fn maintain_cache(&mut self) -> Result<(), Error> {
+        debug!("Cache maintenance run");
+
+        let max_cache_size = get_prepared_statements_cache_size();
+        let mut names = Vec::new();
+
+        while self.prepared_statements.len() >= max_cache_size {
+            // The prepared statmeents are alphanumerically sorted by the BTree.
+            // FIFO.
+            if let Some(name) = self.prepared_statements.pop_last() {
+                names.push(name);
+            }
+        }
+
+        if !names.is_empty() {
+            self.deallocate(names).await?;
+        }
+
+        Ok(())
+    }
+
+    /// Remove the prepared statement from being tracked by this server.
+    /// The client is processing data that will cause the server to close the prepared statement.
+    pub fn will_close(&mut self, name: &str) {
+        debug!("Will close `{}`", name);
+
+        self.prepared_statements.remove(name);
+    }
+
+    /// Close a prepared statement on the server.
+    pub async fn deallocate(&mut self, names: Vec<String>) -> Result<(), Error> {
+        for name in &names {
+            debug!("Deallocating prepared statement `{}`", name);
+
+            let close = Close::new(name);
+            let bytes: BytesMut = close.try_into()?;
+
+            self.send(&bytes).await?;
+        }
+
+        if !names.is_empty() {
+            self.send(&flush()).await?;
+        }
+
+        // Read and discard CloseComplete (3)
+        for name in &names {
+            match read_message(&mut self.stream).await {
+                Ok(_) => {
+                    self.prepared_statements.remove(name);
+                    self.stats.prepared_cache_remove();
+                    debug!("Closed `{}`", name);
+                }
+
+                Err(err) => {
+                    self.bad = true;
+                    return Err(err);
+                }
+            };
+        }
+
+        Ok(())
+    }
+
     /// If the server is still inside a transaction.
     /// If the client disconnects while the server is in a transaction, we will clean it up.
     pub fn in_transaction(&self) -> bool {
@@ -912,6 +1053,10 @@ impl Server {
         self.in_transaction
     }
 
+    pub fn in_copy_mode(&self) -> bool {
+        self.in_copy_mode
+    }
+
     /// We don't buffer all of server responses, e.g. COPY OUT produces too much data.
     /// The client is responsible to call `self.recv()` while this method returns true.
     pub fn is_data_available(&self) -> bool {
@@ -995,7 +1140,7 @@ impl Server {
         // server connection thrashing if clients repeatedly do this.
         // Instead, we ROLLBACK that transaction before putting the connection back in the pool
         if self.in_transaction() {
-            warn!("Server returned while still in transaction, rolling back transaction");
+            warn!(target: "pgcat::server::cleanup", "Server returned while still in transaction, rolling back transaction");
             self.query("ROLLBACK").await?;
         }
 
@@ -1004,13 +1149,17 @@ impl Server {
         // to avoid leaking state between clients. For performance reasons we only
         // send `DISCARD ALL` if we think the session is altered instead of just sending
         // it before each checkin.
-        if self.cleanup_state.needs_cleanup() {
-            warn!("Server returned with session state altered, discarding state ({}) for application {}", self.cleanup_state, self.application_name);
+        if self.cleanup_state.needs_cleanup() && self.cleanup_connections {
+            info!(target: "pgcat::server::cleanup", "Server returned with session state altered, discarding state ({}) for application {}", self.cleanup_state, self.application_name);
             self.query("DISCARD ALL").await?;
             self.query("RESET ROLE").await?;
             self.cleanup_state.reset();
         }
 
+        if self.in_copy_mode() {
+            warn!(target: "pgcat::server::cleanup", "Server returned while still in copy-mode");
+        }
+
         Ok(())
     }
 
@@ -1084,6 +1233,7 @@ impl Server {
             client_server_map,
             Arc::new(ServerStats::default()),
             Arc::new(RwLock::new(None)),
+            true,
         )
         .await?;
         debug!("Connected!, sending query.");

src/stats.rs

@@ -1,4 +1,3 @@
-use crate::pool::PoolIdentifier;
 /// Statistics and reporting.
 use arc_swap::ArcSwap;
 
@@ -16,13 +15,11 @@ pub mod pool;
 pub mod server;
 pub use address::AddressStats;
 pub use client::{ClientState, ClientStats};
-pub use pool::PoolStats;
 pub use server::{ServerState, ServerStats};
 
 /// Convenience types for various stats
 type ClientStatesLookup = HashMap<i32, Arc<ClientStats>>;
 type ServerStatesLookup = HashMap<i32, Arc<ServerStats>>;
-type PoolStatsLookup = HashMap<(String, String), Arc<PoolStats>>;
 
 /// Stats for individual client connections
 /// Used in SHOW CLIENTS.
@@ -34,11 +31,6 @@ static CLIENT_STATS: Lazy<Arc<RwLock<ClientStatesLookup>>> =
 static SERVER_STATS: Lazy<Arc<RwLock<ServerStatesLookup>>> =
     Lazy::new(|| Arc::new(RwLock::new(ServerStatesLookup::default())));
 
-/// Aggregate stats for each pool (a pool is identified by database name and username)
-/// Used in SHOW POOLS.
-static POOL_STATS: Lazy<Arc<RwLock<PoolStatsLookup>>> =
-    Lazy::new(|| Arc::new(RwLock::new(PoolStatsLookup::default())));
-
 /// The statistics reporter. An instance is given to each possible source of statistics,
 /// e.g. client stats, server stats, connection pool stats.
 pub static REPORTER: Lazy<ArcSwap<Reporter>> =
@@ -80,13 +72,6 @@ impl Reporter {
     fn server_disconnecting(&self, server_id: i32) {
         SERVER_STATS.write().remove(&server_id);
     }
-
-    /// Register a pool with the stats system.
-    fn pool_register(&self, identifier: PoolIdentifier, stats: Arc<PoolStats>) {
-        POOL_STATS
-            .write()
-            .insert((identifier.db, identifier.user), stats);
-    }
 }
 
 /// The statistics collector which used for calculating averages
@@ -113,6 +98,7 @@ impl Collector {
                 for stats in server_stats.values() {
                     if !stats.check_address_stat_average_is_updated_status() {
                         stats.address_stats().update_averages();
+                        stats.address_stats().reset_current_counts();
                         stats.set_address_stat_average_is_updated_status(true);
                     }
                 }
@@ -138,12 +124,6 @@ pub fn get_server_stats() -> ServerStatesLookup {
     SERVER_STATS.read().clone()
 }
 
-/// Get a snapshot of pool statistics.
-/// by the `Collector`.
-pub fn get_pool_stats() -> PoolStatsLookup {
-    POOL_STATS.read().clone()
-}
-
 /// Get the statistics reporter used to update stats across the pools/clients.
 pub fn get_reporter() -> Reporter {
     (*(*REPORTER.load())).clone()

src/stats/address.rs

@@ -1,35 +1,26 @@
 use std::sync::atomic::*;
 use std::sync::Arc;
 
+#[derive(Debug, Clone, Default)]
+struct AddressStatFields {
+    xact_count: Arc<AtomicU64>,
+    query_count: Arc<AtomicU64>,
+    bytes_received: Arc<AtomicU64>,
+    bytes_sent: Arc<AtomicU64>,
+    xact_time: Arc<AtomicU64>,
+    query_time: Arc<AtomicU64>,
+    wait_time: Arc<AtomicU64>,
+    errors: Arc<AtomicU64>,
+}
+
 /// Internal address stats
 #[derive(Debug, Clone, Default)]
 pub struct AddressStats {
-    pub total_xact_count: Arc<AtomicU64>,
-    pub total_query_count: Arc<AtomicU64>,
-    pub total_received: Arc<AtomicU64>,
-    pub total_sent: Arc<AtomicU64>,
-    pub total_xact_time: Arc<AtomicU64>,
-    pub total_query_time: Arc<AtomicU64>,
-    pub total_wait_time: Arc<AtomicU64>,
-    pub total_errors: Arc<AtomicU64>,
+    total: AddressStatFields,
 
-    pub old_total_xact_count: Arc<AtomicU64>,
-    pub old_total_query_count: Arc<AtomicU64>,
-    pub old_total_received: Arc<AtomicU64>,
-    pub old_total_sent: Arc<AtomicU64>,
-    pub old_total_xact_time: Arc<AtomicU64>,
-    pub old_total_query_time: Arc<AtomicU64>,
-    pub old_total_wait_time: Arc<AtomicU64>,
-    pub old_total_errors: Arc<AtomicU64>,
+    current: AddressStatFields,
 
-    pub avg_query_count: Arc<AtomicU64>,
-    pub avg_query_time: Arc<AtomicU64>,
-    pub avg_recv: Arc<AtomicU64>,
-    pub avg_sent: Arc<AtomicU64>,
-    pub avg_errors: Arc<AtomicU64>,
-    pub avg_xact_time: Arc<AtomicU64>,
-    pub avg_xact_count: Arc<AtomicU64>,
-    pub avg_wait_time: Arc<AtomicU64>,
+    averages: AddressStatFields,
 
     // Determines if the averages have been updated since the last time they were reported
     pub averages_updated: Arc<AtomicBool>,
@@ -43,67 +34,67 @@ impl IntoIterator for AddressStats {
         vec![
             (
                 "total_xact_count".to_string(),
-                self.total_xact_count.load(Ordering::Relaxed),
+                self.total.xact_count.load(Ordering::Relaxed),
             ),
             (
                 "total_query_count".to_string(),
-                self.total_query_count.load(Ordering::Relaxed),
+                self.total.query_count.load(Ordering::Relaxed),
             ),
             (
                 "total_received".to_string(),
-                self.total_received.load(Ordering::Relaxed),
+                self.total.bytes_received.load(Ordering::Relaxed),
             ),
             (
                 "total_sent".to_string(),
-                self.total_sent.load(Ordering::Relaxed),
+                self.total.bytes_sent.load(Ordering::Relaxed),
             ),
             (
                 "total_xact_time".to_string(),
-                self.total_xact_time.load(Ordering::Relaxed),
+                self.total.xact_time.load(Ordering::Relaxed),
             ),
             (
                 "total_query_time".to_string(),
-                self.total_query_time.load(Ordering::Relaxed),
+                self.total.query_time.load(Ordering::Relaxed),
             ),
             (
                 "total_wait_time".to_string(),
-                self.total_wait_time.load(Ordering::Relaxed),
+                self.total.wait_time.load(Ordering::Relaxed),
             ),
             (
                 "total_errors".to_string(),
-                self.total_errors.load(Ordering::Relaxed),
+                self.total.errors.load(Ordering::Relaxed),
             ),
             (
                 "avg_xact_count".to_string(),
-                self.avg_xact_count.load(Ordering::Relaxed),
+                self.averages.xact_count.load(Ordering::Relaxed),
             ),
             (
                 "avg_query_count".to_string(),
-                self.avg_query_count.load(Ordering::Relaxed),
+                self.averages.query_count.load(Ordering::Relaxed),
             ),
             (
                 "avg_recv".to_string(),
-                self.avg_recv.load(Ordering::Relaxed),
+                self.averages.bytes_received.load(Ordering::Relaxed),
             ),
             (
                 "avg_sent".to_string(),
-                self.avg_sent.load(Ordering::Relaxed),
+                self.averages.bytes_sent.load(Ordering::Relaxed),
             ),
             (
                 "avg_errors".to_string(),
-                self.avg_errors.load(Ordering::Relaxed),
+                self.averages.errors.load(Ordering::Relaxed),
             ),
             (
                 "avg_xact_time".to_string(),
-                self.avg_xact_time.load(Ordering::Relaxed),
+                self.averages.xact_time.load(Ordering::Relaxed),
             ),
             (
                 "avg_query_time".to_string(),
-                self.avg_query_time.load(Ordering::Relaxed),
+                self.averages.query_time.load(Ordering::Relaxed),
             ),
             (
                 "avg_wait_time".to_string(),
-                self.avg_wait_time.load(Ordering::Relaxed),
+                self.averages.wait_time.load(Ordering::Relaxed),
             ),
         ]
         .into_iter()
@@ -111,21 +102,120 @@ impl IntoIterator for AddressStats {
 }
 
 impl AddressStats {
+    pub fn xact_count_add(&self) {
+        self.total.xact_count.fetch_add(1, Ordering::Relaxed);
+        self.current.xact_count.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn query_count_add(&self) {
+        self.total.query_count.fetch_add(1, Ordering::Relaxed);
+        self.current.query_count.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn bytes_received_add(&self, bytes: u64) {
+        self.total
+            .bytes_received
+            .fetch_add(bytes, Ordering::Relaxed);
+        self.current
+            .bytes_received
+            .fetch_add(bytes, Ordering::Relaxed);
+    }
+
+    pub fn bytes_sent_add(&self, bytes: u64) {
+        self.total.bytes_sent.fetch_add(bytes, Ordering::Relaxed);
+        self.current.bytes_sent.fetch_add(bytes, Ordering::Relaxed);
+    }
+
+    pub fn xact_time_add(&self, time: u64) {
+        self.total.xact_time.fetch_add(time, Ordering::Relaxed);
+        self.current.xact_time.fetch_add(time, Ordering::Relaxed);
+    }
+
+    pub fn query_time_add(&self, time: u64) {
+        self.total.query_time.fetch_add(time, Ordering::Relaxed);
+        self.current.query_time.fetch_add(time, Ordering::Relaxed);
+    }
+
+    pub fn wait_time_add(&self, time: u64) {
+        self.total.wait_time.fetch_add(time, Ordering::Relaxed);
+        self.current.wait_time.fetch_add(time, Ordering::Relaxed);
+    }
+
     pub fn error(&self) {
-        self.total_errors.fetch_add(1, Ordering::Relaxed);
+        self.total.errors.fetch_add(1, Ordering::Relaxed);
+        self.current.errors.fetch_add(1, Ordering::Relaxed);
     }
 
     pub fn update_averages(&self) {
-        let (totals, averages, old_totals) = self.fields_iterators();
-        for (total, average, old_total) in itertools::izip!(totals, averages, old_totals) {
-            let total_value = total.load(Ordering::Relaxed);
-            let old_total_value = old_total.load(Ordering::Relaxed);
-            average.store(
-                (total_value - old_total_value) / (crate::stats::STAT_PERIOD / 1_000),
-                Ordering::Relaxed,
-            ); // Avg / second
-            old_total.store(total_value, Ordering::Relaxed);
+        let stat_period_per_second = crate::stats::STAT_PERIOD / 1_000;
+
+        // xact_count
+        let current_xact_count = self.current.xact_count.load(Ordering::Relaxed);
+        let current_xact_time = self.current.xact_time.load(Ordering::Relaxed);
+        self.averages.xact_count.store(
+            current_xact_count / stat_period_per_second,
+            Ordering::Relaxed,
+        );
+        if current_xact_count == 0 {
+            self.averages.xact_time.store(0, Ordering::Relaxed);
+        } else {
+            self.averages
+                .xact_time
+                .store(current_xact_time / current_xact_count, Ordering::Relaxed);
         }
+
+        // query_count
+        let current_query_count = self.current.query_count.load(Ordering::Relaxed);
+        let current_query_time = self.current.query_time.load(Ordering::Relaxed);
+        self.averages.query_count.store(
+            current_query_count / stat_period_per_second,
+            Ordering::Relaxed,
+        );
+        if current_query_count == 0 {
+            self.averages.query_time.store(0, Ordering::Relaxed);
+        } else {
+            self.averages
+                .query_time
+                .store(current_query_time / current_query_count, Ordering::Relaxed);
+        }
+
+        // bytes_received
+        let current_bytes_received = self.current.bytes_received.load(Ordering::Relaxed);
+        self.averages.bytes_received.store(
+            current_bytes_received / stat_period_per_second,
+            Ordering::Relaxed,
+        );
+
+        // bytes_sent
+        let current_bytes_sent = self.current.bytes_sent.load(Ordering::Relaxed);
+        self.averages.bytes_sent.store(
+            current_bytes_sent / stat_period_per_second,
+            Ordering::Relaxed,
+        );
+
+        // wait_time
+        let current_wait_time = self.current.wait_time.load(Ordering::Relaxed);
+        self.averages.wait_time.store(
+            current_wait_time / stat_period_per_second,
+            Ordering::Relaxed,
+        );
+
+        // errors
+        let current_errors = self.current.errors.load(Ordering::Relaxed);
+        self.averages
+            .errors
+            .store(current_errors / stat_period_per_second, Ordering::Relaxed);
+    }
+
+    pub fn reset_current_counts(&self) {
+        self.current.xact_count.store(0, Ordering::Relaxed);
+        self.current.xact_time.store(0, Ordering::Relaxed);
+        self.current.query_count.store(0, Ordering::Relaxed);
+        self.current.query_time.store(0, Ordering::Relaxed);
+        self.current.bytes_received.store(0, Ordering::Relaxed);
+        self.current.bytes_sent.store(0, Ordering::Relaxed);
+        self.current.wait_time.store(0, Ordering::Relaxed);
+        self.current.errors.store(0, Ordering::Relaxed);
     }
 
     pub fn populate_row(&self, row: &mut Vec<String>) {
@@ -133,43 +223,4 @@ impl AddressStats {
             row.push(value.to_string());
         }
     }
-
-    fn fields_iterators(
-        &self,
-    ) -> (
-        Vec<Arc<AtomicU64>>,
-        Vec<Arc<AtomicU64>>,
-        Vec<Arc<AtomicU64>>,
-    ) {
-        let mut totals: Vec<Arc<AtomicU64>> = Vec::new();
-        let mut averages: Vec<Arc<AtomicU64>> = Vec::new();
-        let mut old_totals: Vec<Arc<AtomicU64>> = Vec::new();
-
-        totals.push(self.total_xact_count.clone());
-        old_totals.push(self.old_total_xact_count.clone());
-        averages.push(self.avg_xact_count.clone());
-        totals.push(self.total_query_count.clone());
-        old_totals.push(self.old_total_query_count.clone());
-        averages.push(self.avg_query_count.clone());
-        totals.push(self.total_received.clone());
-        old_totals.push(self.old_total_received.clone());
-        averages.push(self.avg_recv.clone());
-        totals.push(self.total_sent.clone());
-        old_totals.push(self.old_total_sent.clone());
-        averages.push(self.avg_sent.clone());
-        totals.push(self.total_xact_time.clone());
-        old_totals.push(self.old_total_xact_time.clone());
-        averages.push(self.avg_xact_time.clone());
-        totals.push(self.total_query_time.clone());
-        old_totals.push(self.old_total_query_time.clone());
-        averages.push(self.avg_query_time.clone());
-        totals.push(self.total_wait_time.clone());
-        old_totals.push(self.old_total_wait_time.clone());
-        averages.push(self.avg_wait_time.clone());
-        totals.push(self.total_errors.clone());
-        old_totals.push(self.old_total_errors.clone());
-        averages.push(self.avg_errors.clone());
-
-        (totals, averages, old_totals)
-    }
 }

src/stats/client.rs

@@ -1,4 +1,3 @@
-use super::PoolStats;
 use super::{get_reporter, Reporter};
 use atomic_enum::atomic_enum;
 use std::sync::atomic::*;
@@ -34,12 +33,14 @@ pub struct ClientStats {
     pool_name: String,
     connect_time: Instant,
 
-    pool_stats: Arc<PoolStats>,
     reporter: Reporter,
 
     /// Total time spent waiting for a connection from pool, measures in microseconds
     pub total_wait_time: Arc<AtomicU64>,
 
+    /// Maximum time spent waiting for a connection from pool, measures in microseconds
+    pub max_wait_time: Arc<AtomicU64>,
+
     /// Current state of the client
     pub state: Arc<AtomicClientState>,
 
@@ -61,8 +62,8 @@ impl Default for ClientStats {
             application_name: String::new(),
             username: String::new(),
             pool_name: String::new(),
-            pool_stats: Arc::new(PoolStats::default()),
             total_wait_time: Arc::new(AtomicU64::new(0)),
+            max_wait_time: Arc::new(AtomicU64::new(0)),
             state: Arc::new(AtomicClientState::new(ClientState::Idle)),
             transaction_count: Arc::new(AtomicU64::new(0)),
             query_count: Arc::new(AtomicU64::new(0)),
@@ -79,11 +80,9 @@ impl ClientStats {
         username: &str,
         pool_name: &str,
         connect_time: Instant,
-        pool_stats: Arc<PoolStats>,
     ) -> Self {
         Self {
             client_id,
-            pool_stats,
             connect_time,
             application_name: application_name.to_string(),
             username: username.to_string(),
@@ -96,8 +95,6 @@ impl ClientStats {
     /// update metrics on the corresponding pool.
     pub fn disconnect(&self) {
         self.reporter.client_disconnecting(self.client_id);
-        self.pool_stats
-            .client_disconnect(self.state.load(Ordering::Relaxed))
     }
 
     /// Register a client with the stats system. The stats system uses client_id
@@ -105,27 +102,20 @@ impl ClientStats {
     pub fn register(&self, stats: Arc<ClientStats>) {
         self.reporter.client_register(self.client_id, stats);
         self.state.store(ClientState::Idle, Ordering::Relaxed);
-        self.pool_stats.cl_idle.fetch_add(1, Ordering::Relaxed);
     }
 
     /// Reports a client is done querying the server and is no longer assigned a server connection
     pub fn idle(&self) {
-        self.pool_stats
-            .client_idle(self.state.load(Ordering::Relaxed));
         self.state.store(ClientState::Idle, Ordering::Relaxed);
     }
 
     /// Reports a client is waiting for a connection
     pub fn waiting(&self) {
-        self.pool_stats
-            .client_waiting(self.state.load(Ordering::Relaxed));
         self.state.store(ClientState::Waiting, Ordering::Relaxed);
     }
 
     /// Reports a client is done waiting for a connection and is about to query the server.
     pub fn active(&self) {
-        self.pool_stats
-            .client_active(self.state.load(Ordering::Relaxed));
         self.state.store(ClientState::Active, Ordering::Relaxed);
     }
 
@@ -144,6 +134,8 @@ impl ClientStats {
     pub fn checkout_time(&self, microseconds: u64) {
         self.total_wait_time
             .fetch_add(microseconds, Ordering::Relaxed);
+        self.max_wait_time
+            .fetch_max(microseconds, Ordering::Relaxed);
     }
 
     /// Report a query executed by a client against a server

src/stats/pool.rs

@@ -1,36 +1,131 @@
-use crate::config::Pool;
-use crate::config::PoolMode;
-use crate::pool::PoolIdentifier;
-use std::sync::atomic::*;
-use std::sync::Arc;
+use log::debug;
 
-use super::get_reporter;
-use super::Reporter;
 use super::{ClientState, ServerState};
+use crate::{config::PoolMode, messages::DataType, pool::PoolIdentifier};
+use std::collections::HashMap;
+use std::sync::atomic::*;
 
-#[derive(Debug, Clone, Default)]
+use crate::pool::get_all_pools;
+
+#[derive(Debug, Clone)]
 /// A struct that holds information about a Pool .
 pub struct PoolStats {
-    // Pool identifier, cannot be changed after creating the instance
-    identifier: PoolIdentifier,
+    pub identifier: PoolIdentifier,
+    pub mode: PoolMode,
+    pub cl_idle: u64,
+    pub cl_active: u64,
+    pub cl_waiting: u64,
+    pub cl_cancel_req: u64,
+    pub sv_active: u64,
+    pub sv_idle: u64,
+    pub sv_used: u64,
+    pub sv_tested: u64,
+    pub sv_login: u64,
+    pub maxwait: u64,
+}
+impl PoolStats {
+    pub fn new(identifier: PoolIdentifier, mode: PoolMode) -> Self {
+        PoolStats {
+            identifier,
+            mode,
+            cl_idle: 0,
+            cl_active: 0,
+            cl_waiting: 0,
+            cl_cancel_req: 0,
+            sv_active: 0,
+            sv_idle: 0,
+            sv_used: 0,
+            sv_tested: 0,
+            sv_login: 0,
+            maxwait: 0,
+        }
+    }
 
-    // Pool Config, cannot be changed after creating the instance
-    config: Pool,
+    pub fn construct_pool_lookup() -> HashMap<PoolIdentifier, PoolStats> {
+        let mut map: HashMap<PoolIdentifier, PoolStats> = HashMap::new();
+        let client_map = super::get_client_stats();
+        let server_map = super::get_server_stats();
 
-    // A reference to the global reporter.
-    reporter: Reporter,
+        for (identifier, pool) in get_all_pools() {
+            map.insert(
+                identifier.clone(),
+                PoolStats::new(identifier, pool.settings.pool_mode),
+            );
+        }
 
-    /// Counters (atomics)
-    pub cl_idle: Arc<AtomicU64>,
-    pub cl_active: Arc<AtomicU64>,
-    pub cl_waiting: Arc<AtomicU64>,
-    pub cl_cancel_req: Arc<AtomicU64>,
-    pub sv_active: Arc<AtomicU64>,
-    pub sv_idle: Arc<AtomicU64>,
-    pub sv_used: Arc<AtomicU64>,
-    pub sv_tested: Arc<AtomicU64>,
-    pub sv_login: Arc<AtomicU64>,
-    pub maxwait: Arc<AtomicU64>,
+        for client in client_map.values() {
+            match map.get_mut(&PoolIdentifier {
+                db: client.pool_name(),
+                user: client.username(),
+            }) {
+                Some(pool_stats) => {
+                    match client.state.load(Ordering::Relaxed) {
+                        ClientState::Active => pool_stats.cl_active += 1,
+                        ClientState::Idle => pool_stats.cl_idle += 1,
+                        ClientState::Waiting => pool_stats.cl_waiting += 1,
+                    }
+                    let max_wait = client.max_wait_time.load(Ordering::Relaxed);
+                    pool_stats.maxwait = std::cmp::max(pool_stats.maxwait, max_wait);
+                }
+                None => debug!("Client from an obselete pool"),
+            }
+        }
+
+        for server in server_map.values() {
+            match map.get_mut(&PoolIdentifier {
+                db: server.pool_name(),
+                user: server.username(),
+            }) {
+                Some(pool_stats) => match server.state.load(Ordering::Relaxed) {
+                    ServerState::Active => pool_stats.sv_active += 1,
+                    ServerState::Idle => pool_stats.sv_idle += 1,
+                    ServerState::Login => pool_stats.sv_login += 1,
+                    ServerState::Tested => pool_stats.sv_tested += 1,
+                },
+                None => debug!("Server from an obselete pool"),
+            }
+        }
+
+        return map;
+    }
+
+    pub fn generate_header() -> Vec<(&'static str, DataType)> {
+        return vec![
+            ("database", DataType::Text),
+            ("user", DataType::Text),
+            ("pool_mode", DataType::Text),
+            ("cl_idle", DataType::Numeric),
+            ("cl_active", DataType::Numeric),
+            ("cl_waiting", DataType::Numeric),
+            ("cl_cancel_req", DataType::Numeric),
+            ("sv_active", DataType::Numeric),
+            ("sv_idle", DataType::Numeric),
+            ("sv_used", DataType::Numeric),
+            ("sv_tested", DataType::Numeric),
+            ("sv_login", DataType::Numeric),
+            ("maxwait", DataType::Numeric),
+            ("maxwait_us", DataType::Numeric),
+        ];
+    }
+
+    pub fn generate_row(&self) -> Vec<String> {
+        return vec![
+            self.identifier.db.clone(),
+            self.identifier.user.clone(),
+            self.mode.to_string(),
+            self.cl_idle.to_string(),
+            self.cl_active.to_string(),
+            self.cl_waiting.to_string(),
+            self.cl_cancel_req.to_string(),
+            self.sv_active.to_string(),
+            self.sv_idle.to_string(),
+            self.sv_used.to_string(),
+            self.sv_tested.to_string(),
+            self.sv_login.to_string(),
+            (self.maxwait / 1_000_000).to_string(),
+            (self.maxwait % 1_000_000).to_string(),
+        ];
+    }
 }
 
 impl IntoIterator for PoolStats {
@@ -39,236 +134,18 @@ impl IntoIterator for PoolStats {
 
     fn into_iter(self) -> Self::IntoIter {
         vec![
-            ("cl_idle".to_string(), self.cl_idle.load(Ordering::Relaxed)),
-            (
-                "cl_active".to_string(),
-                self.cl_active.load(Ordering::Relaxed),
-            ),
-            (
-                "cl_waiting".to_string(),
-                self.cl_waiting.load(Ordering::Relaxed),
-            ),
-            (
-                "cl_cancel_req".to_string(),
-                self.cl_cancel_req.load(Ordering::Relaxed),
-            ),
-            (
-                "sv_active".to_string(),
-                self.sv_active.load(Ordering::Relaxed),
-            ),
-            ("sv_idle".to_string(), self.sv_idle.load(Ordering::Relaxed)),
-            ("sv_used".to_string(), self.sv_used.load(Ordering::Relaxed)),
-            (
-                "sv_tested".to_string(),
-                self.sv_tested.load(Ordering::Relaxed),
-            ),
-            (
-                "sv_login".to_string(),
-                self.sv_login.load(Ordering::Relaxed),
-            ),
-            (
-                "maxwait".to_string(),
-                self.maxwait.load(Ordering::Relaxed) / 1_000_000,
-            ),
-            (
-                "maxwait_us".to_string(),
-                self.maxwait.load(Ordering::Relaxed) % 1_000_000,
-            ),
+            ("cl_idle".to_string(), self.cl_idle),
+            ("cl_active".to_string(), self.cl_active),
+            ("cl_waiting".to_string(), self.cl_waiting),
+            ("cl_cancel_req".to_string(), self.cl_cancel_req),
+            ("sv_active".to_string(), self.sv_active),
+            ("sv_idle".to_string(), self.sv_idle),
+            ("sv_used".to_string(), self.sv_used),
+            ("sv_tested".to_string(), self.sv_tested),
+            ("sv_login".to_string(), self.sv_login),
+            ("maxwait".to_string(), self.maxwait / 1_000_000),
+            ("maxwait_us".to_string(), self.maxwait % 1_000_000),
         ]
         .into_iter()
     }
 }
-
-impl PoolStats {
-    pub fn new(identifier: PoolIdentifier, config: Pool) -> Self {
-        Self {
-            identifier,
-            config,
-            reporter: get_reporter(),
-            ..Default::default()
-        }
-    }
-
-    // Getters
-    pub fn register(&self, stats: Arc<PoolStats>) {
-        self.reporter.pool_register(self.identifier.clone(), stats);
-    }
-
-    pub fn database(&self) -> String {
-        self.identifier.db.clone()
-    }
-
-    pub fn user(&self) -> String {
-        self.identifier.user.clone()
-    }
-
-    pub fn pool_mode(&self) -> PoolMode {
-        self.config.pool_mode
-    }
-
-    /// Populates an array of strings with counters (used by admin in show pools)
-    pub fn populate_row(&self, row: &mut Vec<String>) {
-        for (_key, value) in self.clone() {
-            row.push(value.to_string());
-        }
-    }
-
-    /// Deletes the maxwait counter, this is done everytime we obtain metrics
-    pub fn clear_maxwait(&self) {
-        self.maxwait.store(0, Ordering::Relaxed);
-    }
-
-    /// Notified when a server of the pool enters login state.
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the server that notifies.
-    pub fn server_login(&self, from: ServerState) {
-        self.sv_login.fetch_add(1, Ordering::Relaxed);
-        if from != ServerState::Login {
-            self.decrease_from_server_state(from);
-        }
-    }
-
-    /// Notified when a server of the pool become 'active'
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the server that notifies.
-    pub fn server_active(&self, from: ServerState) {
-        self.sv_active.fetch_add(1, Ordering::Relaxed);
-        if from != ServerState::Active {
-            self.decrease_from_server_state(from);
-        }
-    }
-
-    /// Notified when a server of the pool become 'tested'
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the server that notifies.
-    pub fn server_tested(&self, from: ServerState) {
-        self.sv_tested.fetch_add(1, Ordering::Relaxed);
-        if from != ServerState::Tested {
-            self.decrease_from_server_state(from);
-        }
-    }
-
-    /// Notified when a server of the pool become 'idle'
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the server that notifies.
-    pub fn server_idle(&self, from: ServerState) {
-        self.sv_idle.fetch_add(1, Ordering::Relaxed);
-        if from != ServerState::Idle {
-            self.decrease_from_server_state(from);
-        }
-    }
-
-    /// Notified when a client of the pool become 'waiting'
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the client that notifies.
-    pub fn client_waiting(&self, from: ClientState) {
-        if from != ClientState::Waiting {
-            self.cl_waiting.fetch_add(1, Ordering::Relaxed);
-            self.decrease_from_client_state(from);
-        }
-    }
-
-    /// Notified when a client of the pool become 'active'
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the client that notifies.
-    pub fn client_active(&self, from: ClientState) {
-        if from != ClientState::Active {
-            self.cl_active.fetch_add(1, Ordering::Relaxed);
-            self.decrease_from_client_state(from);
-        }
-    }
-
-    /// Notified when a client of the pool become 'idle'
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the client that notifies.
-    pub fn client_idle(&self, from: ClientState) {
-        if from != ClientState::Idle {
-            self.cl_idle.fetch_add(1, Ordering::Relaxed);
-            self.decrease_from_client_state(from);
-        }
-    }
-
-    /// Notified when a client disconnects.
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the client that notifies.
-    pub fn client_disconnect(&self, from: ClientState) {
-        let counter = match from {
-            ClientState::Idle => &self.cl_idle,
-            ClientState::Waiting => &self.cl_waiting,
-            ClientState::Active => &self.cl_active,
-        };
-
-        Self::decrease_counter(counter.clone());
-    }
-
-    /// Notified when a server disconnects.
-    ///
-    /// Arguments:
-    ///
-    /// `from`: The state of the client that notifies.
-    pub fn server_disconnect(&self, from: ServerState) {
-        let counter = match from {
-            ServerState::Active => &self.sv_active,
-            ServerState::Idle => &self.sv_idle,
-            ServerState::Login => &self.sv_login,
-            ServerState::Tested => &self.sv_tested,
-        };
-        Self::decrease_counter(counter.clone());
-    }
-
-    // helpers for counter decrease
-    fn decrease_from_server_state(&self, from: ServerState) {
-        let counter = match from {
-            ServerState::Tested => &self.sv_tested,
-            ServerState::Active => &self.sv_active,
-            ServerState::Idle => &self.sv_idle,
-            ServerState::Login => &self.sv_login,
-        };
-        Self::decrease_counter(counter.clone());
-    }
-
-    fn decrease_from_client_state(&self, from: ClientState) {
-        let counter = match from {
-            ClientState::Active => &self.cl_active,
-            ClientState::Idle => &self.cl_idle,
-            ClientState::Waiting => &self.cl_waiting,
-        };
-        Self::decrease_counter(counter.clone());
-    }
-
-    fn decrease_counter(value: Arc<AtomicU64>) {
-        if value.load(Ordering::Relaxed) > 0 {
-            value.fetch_sub(1, Ordering::Relaxed);
-        }
-    }
-}
-
-#[cfg(test)]
-mod test {
-    use super::*;
-
-    #[test]
-    fn test_decrease() {
-        let stat: PoolStats = PoolStats::default();
-        stat.server_login(ServerState::Login);
-        stat.server_idle(ServerState::Login);
-        assert_eq!(stat.sv_login.load(Ordering::Relaxed), 0);
-        assert_eq!(stat.sv_idle.load(Ordering::Relaxed), 1);
-    }
-}

src/stats/server.rs

@@ -1,5 +1,4 @@
 use super::AddressStats;
-use super::PoolStats;
 use super::{get_reporter, Reporter};
 use crate::config::Address;
 use atomic_enum::atomic_enum;
@@ -38,7 +37,6 @@ pub struct ServerStats {
     address: Address,
     connect_time: Instant,
 
-    pool_stats: Arc<PoolStats>,
     reporter: Reporter,
 
     /// Data
@@ -49,6 +47,9 @@ pub struct ServerStats {
     pub transaction_count: Arc<AtomicU64>,
     pub query_count: Arc<AtomicU64>,
     pub error_count: Arc<AtomicU64>,
+    pub prepared_hit_count: Arc<AtomicU64>,
+    pub prepared_miss_count: Arc<AtomicU64>,
+    pub prepared_cache_size: Arc<AtomicU64>,
 }
 
 impl Default for ServerStats {
@@ -57,7 +58,6 @@ impl Default for ServerStats {
             server_id: 0,
             application_name: Arc::new(RwLock::new(String::new())),
             address: Address::default(),
-            pool_stats: Arc::new(PoolStats::default()),
             connect_time: Instant::now(),
             state: Arc::new(AtomicServerState::new(ServerState::Login)),
             bytes_sent: Arc::new(AtomicU64::new(0)),
@@ -66,15 +66,17 @@ impl Default for ServerStats {
             query_count: Arc::new(AtomicU64::new(0)),
             error_count: Arc::new(AtomicU64::new(0)),
             reporter: get_reporter(),
+            prepared_hit_count: Arc::new(AtomicU64::new(0)),
+            prepared_miss_count: Arc::new(AtomicU64::new(0)),
+            prepared_cache_size: Arc::new(AtomicU64::new(0)),
         }
     }
 }
 
 impl ServerStats {
-    pub fn new(address: Address, pool_stats: Arc<PoolStats>, connect_time: Instant) -> Self {
+    pub fn new(address: Address, connect_time: Instant) -> Self {
         Self {
             address,
-            pool_stats,
             connect_time,
             server_id: rand::random::<i32>(),
             ..Default::default()
@@ -96,9 +98,6 @@ impl ServerStats {
     /// Reports a server connection is no longer assigned to a client
     /// and is available for the next client to pick it up
     pub fn idle(&self) {
-        self.pool_stats
-            .server_idle(self.state.load(Ordering::Relaxed));
-
         self.state.store(ServerState::Idle, Ordering::Relaxed);
     }
 
@@ -106,22 +105,16 @@ impl ServerStats {
     /// Also updates metrics on the pool regarding server usage.
     pub fn disconnect(&self) {
         self.reporter.server_disconnecting(self.server_id);
-        self.pool_stats
-            .server_disconnect(self.state.load(Ordering::Relaxed))
     }
 
     /// Reports a server connection is being tested before being given to a client.
     pub fn tested(&self) {
         self.set_undefined_application();
-        self.pool_stats
-            .server_tested(self.state.load(Ordering::Relaxed));
         self.state.store(ServerState::Tested, Ordering::Relaxed);
     }
 
     /// Reports a server connection is attempting to login.
     pub fn login(&self) {
-        self.pool_stats
-            .server_login(self.state.load(Ordering::Relaxed));
         self.state.store(ServerState::Login, Ordering::Relaxed);
         self.set_undefined_application();
     }
@@ -129,8 +122,6 @@ impl ServerStats {
     /// Reports a server connection has been assigned to a client that
     /// is about to query the server
     pub fn active(&self, application_name: String) {
-        self.pool_stats
-            .server_active(self.state.load(Ordering::Relaxed));
         self.state.store(ServerState::Active, Ordering::Relaxed);
         self.set_application(application_name);
     }
@@ -152,11 +143,11 @@ impl ServerStats {
 
     // Helper methods for show_servers
     pub fn pool_name(&self) -> String {
-        self.pool_stats.database()
+        self.address.pool_name.clone()
     }
 
     pub fn username(&self) -> String {
-        self.pool_stats.user()
+        self.address.username.clone()
     }
 
     pub fn address_name(&self) -> String {
@@ -177,27 +168,17 @@ impl ServerStats {
     }
 
     pub fn checkout_time(&self, microseconds: u64, application_name: String) {
-        // Update server stats and address aggergation stats
+        // Update server stats and address aggregation stats
         self.set_application(application_name);
-        self.address
-            .stats
-            .total_wait_time
-            .fetch_add(microseconds, Ordering::Relaxed);
-        self.pool_stats
-            .maxwait
-            .fetch_max(microseconds, Ordering::Relaxed);
+        self.address.stats.wait_time_add(microseconds);
     }
 
     /// Report a query executed by a client against a server
     pub fn query(&self, milliseconds: u64, application_name: &str) {
         self.set_application(application_name.to_string());
-        let address_stats = self.address_stats();
-        address_stats
-            .total_query_count
-            .fetch_add(1, Ordering::Relaxed);
-        address_stats
-            .total_query_time
-            .fetch_add(milliseconds, Ordering::Relaxed);
+        self.address.stats.query_count_add();
+        self.address.stats.query_time_add(milliseconds);
+        self.query_count.fetch_add(1, Ordering::Relaxed);
     }
 
     /// Report a transaction executed by a client a server
@@ -208,29 +189,38 @@ impl ServerStats {
         self.set_application(application_name.to_string());
 
         self.transaction_count.fetch_add(1, Ordering::Relaxed);
-        self.address
-            .stats
-            .total_xact_count
-            .fetch_add(1, Ordering::Relaxed);
+        self.address.stats.xact_count_add();
     }
 
     /// Report data sent to a server
     pub fn data_sent(&self, amount_bytes: usize) {
         self.bytes_sent
             .fetch_add(amount_bytes as u64, Ordering::Relaxed);
-        self.address
-            .stats
-            .total_sent
-            .fetch_add(amount_bytes as u64, Ordering::Relaxed);
+        self.address.stats.bytes_sent_add(amount_bytes as u64);
     }
 
     /// Report data received from a server
     pub fn data_received(&self, amount_bytes: usize) {
         self.bytes_received
             .fetch_add(amount_bytes as u64, Ordering::Relaxed);
-        self.address
-            .stats
-            .total_received
-            .fetch_add(amount_bytes as u64, Ordering::Relaxed);
+        self.address.stats.bytes_received_add(amount_bytes as u64);
+    }
+
+    /// Report a prepared statement that already exists on the server.
+    pub fn prepared_cache_hit(&self) {
+        self.prepared_hit_count.fetch_add(1, Ordering::Relaxed);
+    }
+
+    /// Report a prepared statement that does not exist on the server yet.
+    pub fn prepared_cache_miss(&self) {
+        self.prepared_miss_count.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn prepared_cache_add(&self) {
+        self.prepared_cache_size.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn prepared_cache_remove(&self) {
+        self.prepared_cache_size.fetch_sub(1, Ordering::Relaxed);
     }
 }

tests/python/tests.py

@@ -63,6 +63,7 @@ def cleanup_conn(conn: psycopg2.extensions.connection, cur: psycopg2.extensions.
 
 
 def test_normal_db_access():
+    pgcat_start()
     conn, cur = connect_db(autocommit=False)
     cur.execute("SELECT 1")
     res = cur.fetchall()

tests/ruby/admin_spec.rb

@@ -11,326 +11,6 @@ describe "Admin" do
     processes.pgcat.shutdown
   end
 
-  describe "SHOW STATS" do
-    context "clients connect and make one query" do
-      it "updates *_query_time and *_wait_time" do
-        connections = Array.new(3) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
-        connections.each do |c|
-          Thread.new { c.async_exec("SELECT pg_sleep(0.25)") }
-        end
-        sleep(1)
-        connections.map(&:close)
-
-        # wait for averages to be calculated, we shouldn't do this too often
-        sleep(15.5)
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-        results = admin_conn.async_exec("SHOW STATS")[0]
-        admin_conn.close
-        expect(results["total_query_time"].to_i).to be_within(200).of(750)
-        expect(results["avg_query_time"].to_i).to be_within(20).of(50)
-
-        expect(results["total_wait_time"].to_i).to_not eq(0)
-        expect(results["avg_wait_time"].to_i).to_not eq(0)
-      end
-    end
-  end
-
-  describe "SHOW POOLS" do
-    context "bad credentials" do
-      it "does not change any stats" do
-        bad_password_url = URI(pgcat_conn_str)
-        bad_password_url.password = "wrong"
-        expect { PG::connect("#{bad_password_url.to_s}?application_name=bad_password") }.to raise_error(PG::ConnectionBad)
-
-        sleep(1)
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_idle cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-
-        expect(results["sv_idle"]).to eq("1")
-      end
-    end
-
-    context "bad database name" do
-      it "does not change any stats" do
-        bad_db_url = URI(pgcat_conn_str)
-        bad_db_url.path = "/wrong_db"
-        expect { PG::connect("#{bad_db_url.to_s}?application_name=bad_db") }.to raise_error(PG::ConnectionBad)
-
-        sleep(1)
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_idle cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-
-        expect(results["sv_idle"]).to eq("1")
-      end
-    end
-
-    context "client connects but issues no queries" do
-      it "only affects cl_idle stats" do
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-
-        before_test = admin_conn.async_exec("SHOW POOLS")[0]["sv_idle"]
-        connections = Array.new(20) { PG::connect(pgcat_conn_str) }
-        sleep(1)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-        expect(results["cl_idle"]).to eq("20")
-        expect(results["sv_idle"]).to eq(before_test)
-
-        connections.map(&:close)
-        sleep(1.1)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_active cl_idle cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-        expect(results["sv_idle"]).to eq(before_test)
-      end
-    end
-
-    context "clients connect and make one query" do
-      it "only affects cl_idle, sv_idle stats" do
-        connections = Array.new(5) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
-        connections.each do |c|
-          Thread.new { c.async_exec("SELECT pg_sleep(2.5)") }
-        end
-
-        sleep(1.1)
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_idle cl_waiting cl_cancel_req sv_idle sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-        expect(results["cl_active"]).to eq("5")
-        expect(results["sv_active"]).to eq("5")
-
-        sleep(3)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-        expect(results["cl_idle"]).to eq("5")
-        expect(results["sv_idle"]).to eq("5")
-
-        connections.map(&:close)
-        sleep(1)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_idle cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-        expect(results["sv_idle"]).to eq("5")
-      end
-    end
-
-    context "client connects and opens a transaction and closes connection uncleanly" do
-      it "produces correct statistics" do
-        connections = Array.new(5) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
-        connections.each do |c|
-          Thread.new do
-            c.async_exec("BEGIN")
-            c.async_exec("SELECT pg_sleep(0.01)")
-            c.close
-          end
-        end
-
-        sleep(1.1)
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_idle cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-        expect(results["sv_idle"]).to eq("5")
-      end
-    end
-
-    context "client fail to checkout connection from the pool" do
-      it "counts clients as idle" do
-        new_configs = processes.pgcat.current_config
-        new_configs["general"]["connect_timeout"] = 500
-        new_configs["general"]["ban_time"] = 1
-        new_configs["general"]["shutdown_timeout"] = 1
-        new_configs["pools"]["sharded_db"]["users"]["0"]["pool_size"] = 1
-        processes.pgcat.update_config(new_configs)
-        processes.pgcat.reload_config
-
-        threads = []
-        connections = Array.new(5) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
-        connections.each do |c|
-          threads << Thread.new { c.async_exec("SELECT pg_sleep(1)") rescue PG::SystemError }
-        end
-
-        sleep(2)
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-        expect(results["cl_idle"]).to eq("5")
-        expect(results["sv_idle"]).to eq("1")
-
-        threads.map(&:join)
-        connections.map(&:close)
-      end
-    end
-
-    context "clients connects and disconnect normally" do
-      let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 2) }
-
-      it 'shows the same number of clients before and after' do
-        clients_before = clients_connected_to_pool(processes: processes)
-        threads = []
-        connections = Array.new(4) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
-        connections.each do |c|
-          threads << Thread.new { c.async_exec("SELECT 1") }
-        end
-        clients_between = clients_connected_to_pool(processes: processes)
-        expect(clients_before).not_to eq(clients_between)
-        connections.each(&:close)
-        clients_after = clients_connected_to_pool(processes: processes)
-        expect(clients_before).to eq(clients_after)
-      end
-    end
-
-    context "clients connects and disconnect abruptly" do
-      let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 10) }
-
-      it 'shows the same number of clients before and after' do
-        threads = []
-        connections = Array.new(2) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
-        connections.each do |c|
-          threads << Thread.new { c.async_exec("SELECT 1") }
-        end
-        clients_before = clients_connected_to_pool(processes: processes)
-        random_string = (0...8).map { (65 + rand(26)).chr }.join
-        connection_string = "#{pgcat_conn_str}?application_name=#{random_string}"
-        faulty_client = Process.spawn("psql -Atx #{connection_string} >/dev/null")
-        sleep(1)
-        # psql starts two processes, we only know the pid of the parent, this
-        # ensure both are killed
-        `pkill -9 -f '#{random_string}'`
-        Process.wait(faulty_client)
-        clients_after = clients_connected_to_pool(processes: processes)
-        expect(clients_before).to eq(clients_after)
-      end
-    end
-
-    context "clients overwhelm server pools" do
-      let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 2) }
-
-      it "cl_waiting is updated to show it" do
-        threads = []
-        connections = Array.new(4) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
-        connections.each do |c|
-          threads << Thread.new { c.async_exec("SELECT pg_sleep(1.5)") }
-        end
-
-        sleep(1.1) # Allow time for stats to update
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_idle cl_cancel_req sv_idle sv_used sv_tested sv_login maxwait].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-
-        expect(results["cl_waiting"]).to eq("2")
-        expect(results["cl_active"]).to eq("2")
-        expect(results["sv_active"]).to eq("2")
-
-        sleep(2.5) # Allow time for stats to update
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login].each do |s|
-          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
-        end
-        expect(results["cl_idle"]).to eq("4")
-        expect(results["sv_idle"]).to eq("2")
-
-        threads.map(&:join)
-        connections.map(&:close)
-      end
-
-      it "show correct max_wait" do
-        threads = []
-        connections = Array.new(4) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
-        connections.each do |c|
-          threads << Thread.new { c.async_exec("SELECT pg_sleep(1.5)") }
-        end
-
-        sleep(2.5) # Allow time for stats to update
-        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-
-        expect(results["maxwait"]).to eq("1")
-        expect(results["maxwait_us"].to_i).to be_within(200_000).of(500_000)
-
-        sleep(4.5) # Allow time for stats to update
-        results = admin_conn.async_exec("SHOW POOLS")[0]
-        expect(results["maxwait"]).to eq("0")
-
-        threads.map(&:join)
-        connections.map(&:close)
-      end
-    end
-  end
-
-  describe "SHOW CLIENTS" do
-    it "reports correct number and application names" do
-      conn_str = processes.pgcat.connection_string("sharded_db", "sharding_user")
-      connections = Array.new(20) { |i| PG::connect("#{conn_str}?application_name=app#{i % 5}") }
-
-      admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-      sleep(1) # Wait for stats to be updated
-
-      results = admin_conn.async_exec("SHOW CLIENTS")
-      expect(results.count).to eq(21) # count admin clients
-      expect(results.select { |c| c["application_name"] == "app3" ||  c["application_name"] == "app4" }.count).to eq(8)
-      expect(results.select { |c| c["database"] == "pgcat" }.count).to eq(1)
-
-      connections[0..5].map(&:close)
-      sleep(1) # Wait for stats to be updated
-      results = admin_conn.async_exec("SHOW CLIENTS")
-      expect(results.count).to eq(15)
-
-      connections[6..].map(&:close)
-      sleep(1) # Wait for stats to be updated
-      expect(admin_conn.async_exec("SHOW CLIENTS").count).to eq(1)
-      admin_conn.close
-    end
-
-    it "reports correct number of queries and transactions" do
-      conn_str = processes.pgcat.connection_string("sharded_db", "sharding_user")
-
-      connections = Array.new(2) { |i| PG::connect("#{conn_str}?application_name=app#{i}") }
-      connections.each do |c|
-        c.async_exec("SELECT 1")
-        c.async_exec("SELECT 2")
-        c.async_exec("SELECT 3")
-        c.async_exec("BEGIN")
-        c.async_exec("SELECT 4")
-        c.async_exec("SELECT 5")
-        c.async_exec("COMMIT")
-      end
-
-      admin_conn = PG::connect(processes.pgcat.admin_connection_string)
-      sleep(1) # Wait for stats to be updated
-
-      results = admin_conn.async_exec("SHOW CLIENTS")
-      expect(results.count).to eq(3)
-      normal_client_results = results.reject { |r| r["database"] == "pgcat" }
-      expect(normal_client_results[0]["transaction_count"]).to eq("4")
-      expect(normal_client_results[1]["transaction_count"]).to eq("4")
-      expect(normal_client_results[0]["query_count"]).to eq("7")
-      expect(normal_client_results[1]["query_count"]).to eq("7")
-
-      admin_conn.close
-      connections.map(&:close)
-    end
-  end
-
   describe "Manual Banning" do
     let(:processes) { Helpers::Pgcat.single_shard_setup("sharded_db", 10) }
     before do
@@ -401,7 +81,7 @@ describe "Admin" do
     end
   end
 
-  describe "SHOW users" do
+  describe "SHOW USERS" do
     it "returns the right users" do
       admin_conn = PG::connect(processes.pgcat.admin_connection_string)
       results = admin_conn.async_exec("SHOW USERS")[0]

tests/ruby/copy_spec.rb

@@ -0,0 +1,102 @@
+# frozen_string_literal: true
+require_relative 'spec_helper'
+
+
+describe "COPY Handling" do
+  let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 5) }
+  before do
+    new_configs = processes.pgcat.current_config
+
+    # Allow connections in the pool to expire faster
+    new_configs["general"]["idle_timeout"] = 5
+    processes.pgcat.update_config(new_configs)
+    # We need to kill the old process that was using the default configs
+    processes.pgcat.stop
+    processes.pgcat.start
+    processes.pgcat.wait_until_ready
+  end
+
+  before do
+    processes.all_databases.first.with_connection do |conn|
+      conn.async_exec "CREATE TABLE copy_test_table (a TEXT,b TEXT,c TEXT,d TEXT)"
+    end
+  end
+
+  after do
+    processes.all_databases.first.with_connection do |conn|
+      conn.async_exec "DROP TABLE copy_test_table;"
+    end
+  end
+
+  after do
+    processes.all_databases.map(&:reset)
+    processes.pgcat.shutdown
+  end
+
+  describe "COPY FROM" do
+    context "within transaction" do
+      it "finishes within alloted time" do
+        conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
+        Timeout.timeout(3) do
+          conn.async_exec("BEGIN")
+          conn.copy_data "COPY copy_test_table FROM STDIN CSV" do
+            sleep 0.5
+            conn.put_copy_data "some,data,to,copy\n"
+            conn.put_copy_data "more,data,to,copy\n"
+          end
+          conn.async_exec("COMMIT")
+        end
+
+        res = conn.async_exec("SELECT * FROM copy_test_table").to_a
+        expect(res).to eq([
+          {"a"=>"some", "b"=>"data", "c"=>"to", "d"=>"copy"},
+          {"a"=>"more", "b"=>"data", "c"=>"to", "d"=>"copy"}
+        ])
+      end
+    end
+
+    context "outside transaction" do
+      it "finishes within alloted time" do
+        conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
+        Timeout.timeout(3) do
+          conn.copy_data "COPY copy_test_table FROM STDIN CSV" do
+            sleep 0.5
+            conn.put_copy_data "some,data,to,copy\n"
+            conn.put_copy_data "more,data,to,copy\n"
+          end
+        end
+
+        res = conn.async_exec("SELECT * FROM copy_test_table").to_a
+        expect(res).to eq([
+          {"a"=>"some", "b"=>"data", "c"=>"to", "d"=>"copy"},
+          {"a"=>"more", "b"=>"data", "c"=>"to", "d"=>"copy"}
+        ])
+      end
+    end
+  end
+
+  describe "COPY TO" do
+    before do
+      conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
+      conn.async_exec("BEGIN")
+      conn.copy_data "COPY copy_test_table FROM STDIN CSV" do
+        conn.put_copy_data "some,data,to,copy\n"
+        conn.put_copy_data "more,data,to,copy\n"
+      end
+      conn.async_exec("COMMIT")
+      conn.close
+    end
+
+    it "works" do
+      res = []
+      conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
+      conn.copy_data "COPY copy_test_table TO STDOUT CSV" do
+        while row=conn.get_copy_data
+          res << row
+        end
+      end
+      expect(res).to eq(["some,data,to,copy\n", "more,data,to,copy\n"])
+    end
+  end
+
+end

tests/ruby/helpers/pgcat_helper.rb

@@ -118,7 +118,7 @@ module Helpers
       end
     end
 
-    def self.single_shard_setup(pool_name, pool_size, pool_mode="transaction", lb_mode="random", log_level="info")
+    def self.single_shard_setup(pool_name, pool_size, pool_mode="transaction", lb_mode="random", log_level="info", pool_settings={})
       user = {
         "password" => "sharding_user",
         "pool_size" => pool_size,
@@ -134,28 +134,32 @@ module Helpers
       replica1 = PgInstance.new(8432, user["username"], user["password"], "shard0")
       replica2 = PgInstance.new(9432, user["username"], user["password"], "shard0")
 
+      pool_config = {
+        "default_role" => "any",
+        "pool_mode" => pool_mode,
+        "load_balancing_mode" => lb_mode,
+        "primary_reads_enabled" => false,
+        "query_parser_enabled" => false,
+        "sharding_function" => "pg_bigint_hash",
+        "shards" => {
+          "0" => {
+            "database" => "shard0",
+            "servers" => [
+              ["localhost", primary.port.to_s, "primary"],
+              ["localhost", replica0.port.to_s, "replica"],
+              ["localhost", replica1.port.to_s, "replica"],
+              ["localhost", replica2.port.to_s, "replica"]
+            ]
+          },
+        },
+        "users" => { "0" => user }
+      }
+
+      pool_config = pool_config.merge(pool_settings)
+
       # Main proxy configs
       pgcat_cfg["pools"] = {
-        "#{pool_name}" => {
-          "default_role" => "any",
-          "pool_mode" => pool_mode,
-          "load_balancing_mode" => lb_mode,
-          "primary_reads_enabled" => false,
-          "query_parser_enabled" => false,
-          "sharding_function" => "pg_bigint_hash",
-          "shards" => {
-            "0" => {
-              "database" => "shard0",
-              "servers" => [
-                ["localhost", primary.port.to_s, "primary"],
-                ["localhost", replica0.port.to_s, "replica"],
-                ["localhost", replica1.port.to_s, "replica"],
-                ["localhost", replica2.port.to_s, "replica"]
-              ]
-            },
-          },
-          "users" => { "0" => user }
-        }
+        "#{pool_name}" => pool_config,
       }
       pgcat_cfg["general"]["port"] = pgcat.port
       pgcat.update_config(pgcat_cfg)

tests/ruby/misc_spec.rb

@@ -320,6 +320,31 @@ describe "Miscellaneous" do
         expect(processes.primary.count_query("DISCARD ALL")).to eq(0)
       end
     end
+
+    context "server cleanup disabled" do
+      let(:processes) { Helpers::Pgcat.single_shard_setup("sharded_db", 1, "transaction", "random", "info", { "cleanup_server_connections" => false }) }
+
+      it "will not clean up connection state" do
+        conn = PG::connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
+        processes.primary.reset_stats
+        conn.async_exec("SET statement_timeout TO 1000")
+        conn.close
+
+        puts processes.pgcat.logs
+        expect(processes.primary.count_query("DISCARD ALL")).to eq(0)
+      end
+
+      it "will not clean up prepared statements" do
+        conn = PG::connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
+        processes.primary.reset_stats
+        conn.async_exec("PREPARE prepared_q (int) AS SELECT $1")
+
+        conn.close
+
+        puts processes.pgcat.logs
+        expect(processes.primary.count_query("DISCARD ALL")).to eq(0)
+      end
+    end
   end
 
   describe "Idle client timeout" do

tests/ruby/prepared_spec.rb

@@ -0,0 +1,29 @@
+require_relative 'spec_helper'
+
+describe 'Prepared statements' do
+  let(:processes) { Helpers::Pgcat.three_shard_setup('sharded_db', 5) }
+
+  context 'enabled' do
+    it 'will work over the same connection' do
+      conn = PG.connect(processes.pgcat.connection_string('sharded_db', 'sharding_user'))
+
+      10.times do |i|
+        statement_name = "statement_#{i}"
+        conn.prepare(statement_name, 'SELECT $1::int')
+        conn.exec_prepared(statement_name, [1])
+        conn.describe_prepared(statement_name)
+      end
+    end
+
+    it 'will work with new connections' do
+      10.times do
+        conn = PG.connect(processes.pgcat.connection_string('sharded_db', 'sharding_user'))
+
+        statement_name = 'statement1'
+        conn.prepare('statement1', 'SELECT $1::int')
+        conn.exec_prepared('statement1', [1])
+        conn.describe_prepared('statement1')
+      end
+    end
+  end
+end

tests/ruby/stats_spec.rb

@@ -0,0 +1,369 @@
+# frozen_string_literal: true
+require 'open3'
+require_relative 'spec_helper'
+
+describe "Stats" do
+  let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 10) }
+  let(:pgcat_conn_str) { processes.pgcat.connection_string("sharded_db", "sharding_user") }
+
+  after do
+    processes.all_databases.map(&:reset)
+    processes.pgcat.shutdown
+  end
+
+  describe "SHOW STATS" do
+    context "clients connect and make one query" do
+      it "updates *_query_time and *_wait_time" do
+        connections = Array.new(3) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          Thread.new { c.async_exec("SELECT pg_sleep(0.25)") }
+        end
+        sleep(1)
+        connections.map(&:close)
+
+        # wait for averages to be calculated, we shouldn't do this too often
+        sleep(15.5)
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW STATS")[0]
+        admin_conn.close
+        expect(results["total_query_time"].to_i).to be_within(200).of(750)
+        expect(results["avg_query_time"].to_i).to be_within(50).of(250)
+
+        expect(results["total_wait_time"].to_i).to_not eq(0)
+        expect(results["avg_wait_time"].to_i).to_not eq(0)
+      end
+    end
+  end
+
+  describe "SHOW POOLS" do
+    context "bad credentials" do
+      it "does not change any stats" do
+        bad_password_url = URI(pgcat_conn_str)
+        bad_password_url.password = "wrong"
+        expect { PG::connect("#{bad_password_url.to_s}?application_name=bad_password") }.to raise_error(PG::ConnectionBad)
+
+        sleep(1)
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_idle cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+
+        expect(results["sv_idle"]).to eq("1")
+      end
+    end
+
+    context "bad database name" do
+      it "does not change any stats" do
+        bad_db_url = URI(pgcat_conn_str)
+        bad_db_url.path = "/wrong_db"
+        expect { PG::connect("#{bad_db_url.to_s}?application_name=bad_db") }.to raise_error(PG::ConnectionBad)
+
+        sleep(1)
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_idle cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+
+        expect(results["sv_idle"]).to eq("1")
+      end
+    end
+
+    context "client connects but issues no queries" do
+      it "only affects cl_idle stats" do
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+
+        before_test = admin_conn.async_exec("SHOW POOLS")[0]["sv_idle"]
+        connections = Array.new(20) { PG::connect(pgcat_conn_str) }
+        sleep(1)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+        expect(results["cl_idle"]).to eq("20")
+        expect(results["sv_idle"]).to eq(before_test)
+
+        connections.map(&:close)
+        sleep(1.1)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_active cl_idle cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+        expect(results["sv_idle"]).to eq(before_test)
+      end
+    end
+
+    context "clients connect and make one query" do
+      it "only affects cl_idle, sv_idle stats" do
+        connections = Array.new(5) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          Thread.new { c.async_exec("SELECT pg_sleep(2.5)") }
+        end
+
+        sleep(1.1)
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_idle cl_waiting cl_cancel_req sv_idle sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+        expect(results["cl_active"]).to eq("5")
+        expect(results["sv_active"]).to eq("5")
+
+        sleep(3)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+        expect(results["cl_idle"]).to eq("5")
+        expect(results["sv_idle"]).to eq("5")
+
+        connections.map(&:close)
+        sleep(1)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_idle cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+        expect(results["sv_idle"]).to eq("5")
+      end
+    end
+
+    context "client connects and opens a transaction and closes connection uncleanly" do
+      it "produces correct statistics" do
+        connections = Array.new(5) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          Thread.new do
+            c.async_exec("BEGIN")
+            c.async_exec("SELECT pg_sleep(0.01)")
+            c.close
+          end
+        end
+
+        sleep(1.1)
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_idle cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+        expect(results["sv_idle"]).to eq("5")
+      end
+    end
+
+    context "client fail to checkout connection from the pool" do
+      it "counts clients as idle" do
+        new_configs = processes.pgcat.current_config
+        new_configs["general"]["connect_timeout"] = 500
+        new_configs["general"]["ban_time"] = 1
+        new_configs["general"]["shutdown_timeout"] = 1
+        new_configs["pools"]["sharded_db"]["users"]["0"]["pool_size"] = 1
+        processes.pgcat.update_config(new_configs)
+        processes.pgcat.reload_config
+
+        threads = []
+        connections = Array.new(5) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          threads << Thread.new { c.async_exec("SELECT pg_sleep(1)") rescue PG::SystemError }
+        end
+
+        sleep(2)
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+        expect(results["cl_idle"]).to eq("5")
+        expect(results["sv_idle"]).to eq("1")
+
+        threads.map(&:join)
+        connections.map(&:close)
+      end
+    end
+
+    context "clients connects and disconnect normally" do
+      let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 2) }
+
+      it 'shows the same number of clients before and after' do
+        clients_before = clients_connected_to_pool(processes: processes)
+        threads = []
+        connections = Array.new(4) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          threads << Thread.new { c.async_exec("SELECT 1") rescue nil }
+        end
+        clients_between = clients_connected_to_pool(processes: processes)
+        expect(clients_before).not_to eq(clients_between)
+        connections.each(&:close)
+        clients_after = clients_connected_to_pool(processes: processes)
+        expect(clients_before).to eq(clients_after)
+      end
+    end
+
+    context "clients connects and disconnect abruptly" do
+      let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 10) }
+
+      it 'shows the same number of clients before and after' do
+        threads = []
+        connections = Array.new(2) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          threads << Thread.new { c.async_exec("SELECT 1") }
+        end
+        clients_before = clients_connected_to_pool(processes: processes)
+        random_string = (0...8).map { (65 + rand(26)).chr }.join
+        connection_string = "#{pgcat_conn_str}?application_name=#{random_string}"
+        faulty_client = Process.spawn("psql -Atx #{connection_string} >/dev/null")
+        sleep(1)
+        # psql starts two processes, we only know the pid of the parent, this
+        # ensure both are killed
+        `pkill -9 -f '#{random_string}'`
+        Process.wait(faulty_client)
+        clients_after = clients_connected_to_pool(processes: processes)
+        expect(clients_before).to eq(clients_after)
+      end
+    end
+
+    context "clients overwhelm server pools" do
+      let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 2) }
+
+      it "cl_waiting is updated to show it" do
+        threads = []
+        connections = Array.new(4) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          threads << Thread.new { c.async_exec("SELECT pg_sleep(1.5)") }
+        end
+
+        sleep(1.1) # Allow time for stats to update
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_idle cl_cancel_req sv_idle sv_used sv_tested sv_login maxwait].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+
+        expect(results["cl_waiting"]).to eq("2")
+        expect(results["cl_active"]).to eq("2")
+        expect(results["sv_active"]).to eq("2")
+
+        sleep(2.5) # Allow time for stats to update
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+        expect(results["cl_idle"]).to eq("4")
+        expect(results["sv_idle"]).to eq("2")
+
+        threads.map(&:join)
+        connections.map(&:close)
+      end
+
+      it "show correct max_wait" do
+        threads = []
+        connections = Array.new(4) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          threads << Thread.new { c.async_exec("SELECT pg_sleep(1.5)") rescue nil }
+        end
+
+        sleep(2.5) # Allow time for stats to update
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+
+        expect(results["maxwait"]).to eq("1")
+        expect(results["maxwait_us"].to_i).to be_within(200_000).of(500_000)
+        connections.map(&:close)
+
+        sleep(4.5) # Allow time for stats to update
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        expect(results["maxwait"]).to eq("0")
+
+        threads.map(&:join)
+      end
+    end
+  end
+
+  describe "SHOW CLIENTS" do
+    it "reports correct number and application names" do
+      conn_str = processes.pgcat.connection_string("sharded_db", "sharding_user")
+      connections = Array.new(20) { |i| PG::connect("#{conn_str}?application_name=app#{i % 5}") }
+
+      admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+      sleep(1) # Wait for stats to be updated
+
+      results = admin_conn.async_exec("SHOW CLIENTS")
+      expect(results.count).to eq(21) # count admin clients
+      expect(results.select { |c| c["application_name"] == "app3" ||  c["application_name"] == "app4" }.count).to eq(8)
+      expect(results.select { |c| c["database"] == "pgcat" }.count).to eq(1)
+
+      connections[0..5].map(&:close)
+      sleep(1) # Wait for stats to be updated
+      results = admin_conn.async_exec("SHOW CLIENTS")
+      expect(results.count).to eq(15)
+
+      connections[6..].map(&:close)
+      sleep(1) # Wait for stats to be updated
+      expect(admin_conn.async_exec("SHOW CLIENTS").count).to eq(1)
+      admin_conn.close
+    end
+
+    it "reports correct number of queries and transactions" do
+      conn_str = processes.pgcat.connection_string("sharded_db", "sharding_user")
+
+      connections = Array.new(2) { |i| PG::connect("#{conn_str}?application_name=app#{i}") }
+      connections.each do |c|
+        c.async_exec("SELECT 1")
+        c.async_exec("SELECT 2")
+        c.async_exec("SELECT 3")
+        c.async_exec("BEGIN")
+        c.async_exec("SELECT 4")
+        c.async_exec("SELECT 5")
+        c.async_exec("COMMIT")
+      end
+
+      admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+      sleep(1) # Wait for stats to be updated
+
+      results = admin_conn.async_exec("SHOW CLIENTS")
+      expect(results.count).to eq(3)
+      normal_client_results = results.reject { |r| r["database"] == "pgcat" }
+      expect(normal_client_results[0]["transaction_count"]).to eq("4")
+      expect(normal_client_results[1]["transaction_count"]).to eq("4")
+      expect(normal_client_results[0]["query_count"]).to eq("7")
+      expect(normal_client_results[1]["query_count"]).to eq("7")
+
+      admin_conn.close
+      connections.map(&:close)
+    end
+  end
+
+
+  describe "Query Storm" do
+    context "when the proxy receives overwhelmingly large number of short quick queries" do
+      it "should not have lingering clients or active servers" do
+        new_configs = processes.pgcat.current_config
+
+        new_configs["general"]["connect_timeout"] = 500
+        new_configs["general"]["ban_time"] = 1
+        new_configs["general"]["shutdown_timeout"] = 1
+        new_configs["pools"]["sharded_db"]["users"]["0"]["pool_size"] = 1
+        processes.pgcat.update_config(new_configs)
+        processes.pgcat.reload_config
+
+        Array.new(40) do
+          Thread.new do
+            conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
+            conn.async_exec("SELECT pg_sleep(0.1)")
+          rescue PG::SystemError
+          ensure
+            conn.close
+          end
+        end.each(&:join)
+
+        sleep 1
+
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        results = admin_conn.async_exec("SHOW POOLS")[0]
+        %w[cl_idle cl_waiting cl_cancel_req sv_used sv_tested sv_login].each do |s|
+          raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
+        end
+
+        admin_conn.close
+      end
+    end
+  end
+end

tests/rust/.gitignore

@@ -0,0 +1 @@
+target/

tests/rust/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "rust"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+sqlx = { version = "0.6.2", features = [ "runtime-tokio-rustls", "postgres", "json", "tls", "migrate", "time", "uuid", "ipnetwork"] }
+tokio = { version = "1", features = ["full"] }

tests/rust/src/main.rs

@@ -0,0 +1,29 @@
+#[tokio::main]
+async fn main() {
+    test_prepared_statements().await;
+}
+
+async fn test_prepared_statements() {
+    let pool = sqlx::postgres::PgPoolOptions::new()
+        .max_connections(5)
+        .connect("postgres://sharding_user:sharding_user@127.0.0.1:6432/sharded_db")
+        .await
+        .unwrap();
+
+    let mut handles = Vec::new();
+
+    for _ in 0..5 {
+        let pool = pool.clone();
+        let handle = tokio::task::spawn(async move {
+            for _ in 0..1000 {
+                sqlx::query("SELECT 1").fetch_all(&pool).await.unwrap();
+            }
+        });
+
+        handles.push(handle);
+    }
+
+    for handle in handles {
+        handle.await.unwrap();
+    }
+}

utilities/deb.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+#
+# Build an Ubuntu deb.
+#
+script_dir=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
+deb_dir="/tmp/pgcat-build"
+export PACKAGE_VERSION=${1:-"1.1.1"}
+if [[ $(arch) == "x86_64" ]]; then
+  export ARCH=amd64
+else
+  export ARCH=arm64
+fi
+
+cd "$script_dir/.."
+cargo build --release
+
+rm -rf "$deb_dir"
+mkdir -p "$deb_dir/DEBIAN"
+mkdir -p "$deb_dir/usr/bin"
+mkdir -p "$deb_dir/etc"
+
+cp target/release/pgcat "$deb_dir/usr/bin/pgcat"
+chmod +x "$deb_dir/usr/bin/pgcat"
+
+cp pgcat.toml "$deb_dir/etc/pgcat.toml"
+
+(cat control | envsubst) > "$deb_dir/DEBIAN/control"
+
+dpkg-deb \
+  --root-owner-group \
+  -z1 \
+  --build "$deb_dir" \
+  pgcat-${PACKAGE_VERSION}-ubuntu22.04-${ARCH}.deb