Experiment: removing shrink_to_fit calls to avoid reallocation.

src/rust/lqosd/src/throughput_tracker/flow_data/flow_analysis/finished_flows.rs

@@ -60,7 +60,6 @@ impl TimeBuffer {
             let one_minute_ago = now - 60;
             let mut buffer = self.buffer.lock().unwrap();
             buffer.retain(|v| v.time > one_minute_ago);
-            buffer.shrink_to_fit();
         }
     }
 

src/rust/lqosd/src/throughput_tracker/flow_data/flow_analysis/kernel_ringbuffer.rs

@@ -164,7 +164,6 @@ impl FlowActor {
                                         let since_boot = Duration::from(now);
                                         let expire = (since_boot - Duration::from_secs(30)).as_nanos() as u64;
                                         flows.flow_rtt.retain(|_, v| v.last_seen > expire);
-                                        flows.flow_rtt.shrink_to_fit();
                                     }
                                 }
                                 Ok(FlowCommands::RttMap(reply)) => {

src/rust/lqosd/src/throughput_tracker/tracking_data.rs

@@ -344,7 +344,6 @@ impl ThroughputTracker {
             let _ = sender.send((key.clone(), (d.0.clone(), d.1.clone())));
           }
         }
-        all_flows_lock.shrink_to_fit();
 
         let ret = lqos_sys::end_flows(expired_keys);
         if let Err(e) = ret {
@@ -355,7 +354,6 @@ impl ThroughputTracker {
       // Cleaning run
       all_flows_lock.retain(|_k,v| v.0.last_seen >= expire);
       expire_rtt_flows();
-      self.raw_data.shrink_to_fit();
     }
   }
 
@@ -405,7 +403,6 @@ impl ThroughputTracker {
 
   pub(crate) fn next_cycle(&self) {
     self.cycle.fetch_add(1, std::sync::atomic::Ordering::Relaxed);
-    self.raw_data.shrink_to_fit();
   }
 
   pub(crate) fn bits_per_second(&self) -> DownUpOrder<u64> {

src/rust/lts_client/src/collector/collation/mod.rs

@@ -144,5 +144,4 @@ pub(crate) async fn collate_stats(comm_tx: Sender<SenderChannelMessage>) {
 
     // Clear the collection buffer
     writer.clear();
-    writer.shrink_to_fit();
 }

src/rust/lts_client/src/submission_queue/queue.rs

@@ -98,7 +98,6 @@ pub(crate) async fn send_queue(stream: &mut TcpStream) -> Result<(), QueueError>
     }
 
     lock.clear();
-    lock.shrink_to_fit();
     Ok(())
 }