Fix lost statistics (#125)

* Lost events

* more logging

src/main.rs

@@ -133,7 +133,7 @@ async fn main() {
     let client_server_map: ClientServerMap = Arc::new(Mutex::new(HashMap::new()));
 
     // Statistics reporting.
-    let (tx, rx) = mpsc::channel(100);
+    let (tx, rx) = mpsc::channel(100_000);
     REPORTER.store(Arc::new(Reporter::new(tx.clone())));
 
     // Connection pool that allows to query all shards and replicas.

src/stats.rs

@@ -1,9 +1,10 @@
 use arc_swap::ArcSwap;
 /// Statistics and reporting.
-use log::info;
+use log::{error, info, trace};
 use once_cell::sync::Lazy;
 use parking_lot::Mutex;
 use std::collections::HashMap;
+use tokio::sync::mpsc::error::TrySendError;
 use tokio::sync::mpsc::{channel, Receiver, Sender};
 
 use crate::pool::get_number_of_addresses;
@@ -43,7 +44,7 @@ enum EventName {
 
 /// Event data sent to the collector
 /// from clients and servers.
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct Event {
     /// The name of the event being reported.
     name: EventName,
@@ -79,6 +80,25 @@ impl Reporter {
         Reporter { tx: tx }
     }
 
+    /// Send statistics to the task keeping track of stats.
+    fn send(&self, event: Event) {
+        let name = event.name;
+        let result = self.tx.try_send(event);
+
+        match result {
+            Ok(_) => trace!(
+                "{:?} event reported successfully, capacity: {}",
+                name,
+                self.tx.capacity()
+            ),
+
+            Err(err) => match err {
+                TrySendError::Full { .. } => error!("{:?} event dropped, buffer full", name),
+                TrySendError::Closed { .. } => error!("{:?} event dropped, channel closed", name),
+            },
+        };
+    }
+
     /// Report a query executed by a client against
     /// a server identified by the `address_id`.
     pub fn query(&self, process_id: i32, address_id: usize) {
@@ -89,7 +109,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event);
     }
 
     /// Report a transaction executed by a client against
@@ -102,7 +122,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Report data sent to a server identified by `address_id`.
@@ -115,7 +135,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Report data received from a server identified by `address_id`.
@@ -128,7 +148,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Time spent waiting to get a healthy connection from the pool
@@ -142,7 +162,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a client identified by `process_id` waiting for a connection
@@ -155,7 +175,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a client identified by `process_id` is done waiting for a connection
@@ -168,7 +188,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a client identified by `process_id` is done querying the server
@@ -181,7 +201,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a client identified by `process_id` is disconecting from the pooler.
@@ -194,7 +214,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a server connection identified by `process_id` for
@@ -208,7 +228,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a server connection identified by `process_id` for
@@ -222,7 +242,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a server connection identified by `process_id` for
@@ -236,7 +256,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a server connection identified by `process_id` for
@@ -250,7 +270,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 
     /// Reports a server connection identified by `process_id` is disconecting from the pooler.
@@ -263,7 +283,7 @@ impl Reporter {
             address_id: address_id,
         };
 
-        let _ = self.tx.try_send(event);
+        self.send(event)
     }
 }