Suppress ExecutionContext while creating timers

vonzshik · vonzshik · commit 525565561fd9 · 2025-09-10T14:39:07.000+03:00
diff --git a/src/Npgsql/Internal/NpgsqlConnector.cs b/src/Npgsql/Internal/NpgsqlConnector.cs
@@ -400,7 +400,10 @@ internal NpgsqlConnector(NpgsqlDataSource dataSource, NpgsqlConnection conn)
 
         _isKeepAliveEnabled = Settings.KeepAlive > 0;
         if (_isKeepAliveEnabled)
-            _keepAliveTimer = new Timer(PerformKeepAlive, null, Timeout.Infinite, Timeout.Infinite);
+        {
+            using (ExecutionContext.SuppressFlow()) // Don't capture the current ExecutionContext and its AsyncLocals onto the timer causing them to live forever
+                _keepAliveTimer = new Timer(PerformKeepAlive, null, Timeout.Infinite, Timeout.Infinite);
+        }
 
         DataReader = new NpgsqlDataReader(this);
 
diff --git a/src/Npgsql/NpgsqlDataSource.cs b/src/Npgsql/NpgsqlDataSource.cs
@@ -124,8 +124,9 @@ internal NpgsqlDataSource(
 
             _timerPasswordProviderCancellationTokenSource = new();
 
-            // Create the timer, but don't start it; the manual run below will will schedule the first refresh.
-            _periodicPasswordProviderTimer = new Timer(state => _ = RefreshPassword(), null, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
+            // Create the timer, but don't start it; the manual run below will schedule the first refresh.
+            using (ExecutionContext.SuppressFlow()) // Don't capture the current ExecutionContext and its AsyncLocals onto the timer causing them to live forever
+                _periodicPasswordProviderTimer = new Timer(state => _ = RefreshPassword(), null, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
             // Trigger the first refresh attempt right now, outside the timer; this allows us to capture the Task so it can be observed
             // in GetPasswordAsync.
             _passwordRefreshTask = Task.Run(RefreshPassword);
diff --git a/src/Npgsql/PoolingDataSource.cs b/src/Npgsql/PoolingDataSource.cs
@@ -97,7 +97,8 @@ internal PoolingDataSource(
         if (connectionIdleLifetime < pruningSamplingInterval)
             throw new ArgumentException($"Connection can't have {nameof(settings.ConnectionIdleLifetime)} {connectionIdleLifetime} under {nameof(settings.ConnectionPruningInterval)} {pruningSamplingInterval}");
 
-        _pruningTimer = new Timer(PruningTimerCallback, this, Timeout.Infinite, Timeout.Infinite);
+        using (ExecutionContext.SuppressFlow()) // Don't capture the current ExecutionContext and its AsyncLocals onto the timer causing them to live forever
+            _pruningTimer = new Timer(PruningTimerCallback, this, Timeout.Infinite, Timeout.Infinite);
         _pruningSampleSize = DivideRoundingUp(settings.ConnectionIdleLifetime, settings.ConnectionPruningInterval);
         _pruningMedianIndex = DivideRoundingUp(_pruningSampleSize, 2) - 1; // - 1 to go from length to index
         _pruningSamplingInterval = pruningSamplingInterval;
diff --git a/src/Npgsql/Replication/ReplicationConnection.cs b/src/Npgsql/Replication/ReplicationConnection.cs
@@ -452,8 +452,11 @@ internal async IAsyncEnumerator<XLogDataMessage> StartReplicationInternal(
 
             SetTimeouts(_walReceiverTimeout, CommandTimeout);
 
-            _sendFeedbackTimer = new Timer(TimerSendFeedback, state: null, WalReceiverStatusInterval, Timeout.InfiniteTimeSpan);
-            _requestFeedbackTimer = new Timer(TimerRequestFeedback, state: null, _requestFeedbackInterval, Timeout.InfiniteTimeSpan);
+            using (ExecutionContext.SuppressFlow()) // Don't capture the current ExecutionContext and its AsyncLocals onto the timer causing them to live forever
+            {
+                _sendFeedbackTimer = new Timer(TimerSendFeedback, state: null, WalReceiverStatusInterval, Timeout.InfiniteTimeSpan);
+                _requestFeedbackTimer = new Timer(TimerRequestFeedback, state: null, _requestFeedbackInterval, Timeout.InfiniteTimeSpan);
+            }
 
             while (true)
             {
