Skip to content

Suppress ExecutionContext while creating timers #6106

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
vonzshik merged 1 commit into from
Oct 1, 2025
Merged

Suppress ExecutionContext while creating timers #6106

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 4 additions & 1 deletion src/Npgsql/Internal/NpgsqlConnector.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -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);

Expand Down
5 changes: 3 additions & 2 deletions src/Npgsql/NpgsqlDataSource.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -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

@vonzshik vonzshik May 5, 2025

Copy link
Copy Markdown
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

We might want to extend that so the first refresh attempt behaves the exact same way as the later ones.

_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);
Expand Down
3 changes: 2 additions & 1 deletion src/Npgsql/PoolingDataSource.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand Down
7 changes: 5 additions & 2 deletions src/Npgsql/Replication/ReplicationConnection.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -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

@vonzshik vonzshik May 5, 2025

Copy link
Copy Markdown
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Strictly speaking, this shouldn't really be necessary since this is IAsyncEnumerator and timers will be disposed whenever the enumerator is, but might as well do this for consistency.

{
_sendFeedbackTimer = new Timer(TimerSendFeedback, state: null, WalReceiverStatusInterval, Timeout.InfiniteTimeSpan);
_requestFeedbackTimer = new Timer(TimerRequestFeedback, state: null, _requestFeedbackInterval, Timeout.InfiniteTimeSpan);
}

while (true)
{
Expand Down