feat: add application-level keepalive to prevent ALB idle connection timeouts#1739
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WhitWaldo merged 3 commits intodapr:masterfrom Apr 5, 2026
Merged
feat: add application-level keepalive to prevent ALB idle connection timeouts#1739WhitWaldo merged 3 commits intodapr:masterfrom
WhitWaldo merged 3 commits intodapr:masterfrom
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Pull request overview
Adds an application-level keepalive mechanism to the workflow worker’s gRPC connection so idle connections aren’t dropped by L7 load balancers (e.g., AWS ALB) that don’t forward HTTP/2 PING frames.
Changes:
- Start a background keepalive loop alongside the existing server-stream receive loop.
- Implement
KeepaliveLoopAsyncto periodically call the existingHelloRPC. - Add a debug log event for keepalive failures.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.
| File | Description |
|---|---|
src/Dapr.Workflow/Worker/Grpc/GrpcProtocolHandler.cs |
Starts/stops a background keepalive task and implements periodic Hello calls. |
src/Dapr.Workflow/Logging.cs |
Adds a new generated log message for keepalive failures. |
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…timeouts AWS ALBs do not forward HTTP/2 PING frames, causing idle gRPC connections to be closed. This adds a background loop that periodically calls the existing Hello RPC as application-level traffic to keep the connection alive through L7 load balancers. Signed-off-by: joshvanl <me@joshvanl.dev>
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Contributor
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Do note that I just merged a PR to support xUnit v3 so your unit/integration tests may need a refresh. |
WhitWaldo
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Apr 5, 2026
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Looks good - thank you for putting this together!
This was referenced Apr 8, 2026
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AWS ALBs do not forward HTTP/2 PING frames, causing idle gRPC connections to be closed. This adds a background loop that periodically calls the existing Hello RPC as application-level traffic to keep the connection alive through L7 load balancers.