fix(buffer_worker): avoid sending late reply messages to callers #10455
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thalesmg
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zmstone
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ieQu1
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| @@ -295,19 +295,19 @@ pick_call(Id, Key, Query, Timeout) -> | |||
| ?PICK(Id, Key, Pid, begin | |||
| Caller = self(), | |||
| MRef = erlang:monitor(process, Pid, [{alias, reply_demonitor}]), | |||
| From = {Caller, MRef}, | |||
| From = {Caller, [alias | MRef]}, | |||
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This function is pretty complicated, it would be great to explain what's going on in a comment.
Q: why does From contain an improper list?
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I'll drop the usage of gen_statem:reply and go back to my first solution of just sending to MRef the reply, after Stone's comment above.
Fixes https://emqx.atlassian.net/browse/EMQX-9635 During a sync call from process `A` to a buffer worker `B`, its call to the underlying resource `C` can be very slow. In those cases, `A` will receive a timeout response and expect no more messages from `B` nor `C`. However, prior to this fix, if `B` is stuck in a long sync call to `C` and then gets its response after `A` timed out, `B` would still send the late response to `A`, polluting its mailbox.
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zmstone
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Pull Request Test Coverage Report for Build 4748080857
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Fixes https://emqx.atlassian.net/browse/EMQX-9635
During a sync call from process
Ato a buffer workerB, its call to the underlying resourceCcan be very slow. In those cases,Awill receive a timeout response and expect no more messages fromBnorC. However, prior to this fix, ifBis stuck in a long sync call toCand then gets its response afterAtimed out,Bwould still send the late response toA, polluting its mailbox.Summary
馃 Generated by Copilot at 8b5521b
Added a new function
reply_call/2toemqx_resource_buffer_workermodule to improve query request handling and tracing. Updated the version number of theemqx_resourceapplication. Added test cases for timeout and late reply scenarios using theemqx_connector_demomodule.PR Checklist
Please convert it to a draft if any of the following conditions are not met. Reviewers may skip over until all the items are checked:
changes/{ce,ee}/(feat|perf|fix)-<PR-id>.en.mdfilesChecklist for CI (.github/workflows) changes
changes/dir for user-facing artifacts update