fix: deadlock in loki.source.file when target is removed#3488
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kalleep
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| opts component.Options | ||
| metrics *metrics | ||
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| updateMut sync.Mutex |
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This was only used in Update so we don't need it
wildum
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* Fix deadlock that can happen when stopping reader tasks Co-authored-by: William Dumont <william.dumont@grafana.com>
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* fix: panic that happens when a target gets deleted when using decompression (#3475) * Fix panic caused that can happen when when file is removed for decompressor * Change to start readLine start and stops updatePositions * Add changelog * Fix mimir.rules.kubernetes panic on non-leader debug info retrieval (#3451) * Fix mimir.rules.kubernetes to only return eventProcessor state if it exists * fix: deadlock in loki.source.file when target is removed (#3488) * Fix deadlock that can happen when stopping reader tasks Co-authored-by: William Dumont <william.dumont@grafana.com> * fix: emit valid logfmt key (#3495) * Fix log keys to be valid for logfmt * Add changelog * Fix streams limit error check so that metrics are correctly labeled as `ReasonStreamLimited` (#3466) * fix: replace direct error string compare with isErrMaxStreamsLimitExceeded helper * update CHANGELOG * Make errMaxStreamsLimitExceeded an error type --------- Co-authored-by: Théo Brigitte <theo.brigitte@gmail.com> Co-authored-by: William Dumont <william.dumont@grafana.com> Co-authored-by: Marat Khvostov <marathvostov@gmail.com>
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* Fix deadlock that can happen when stopping reader tasks Co-authored-by: William Dumont <william.dumont@grafana.com>
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PR Description
#3456 reports that some alloy nodes stopped sending logs. Alloy itself still produced some logs looking like this:
Trying to access
/api/v0/web/componentshangs and the profile shows that most go routines are parked. This is most likely symptoms of a deadlock.While going through the changes we have made to this component I noticed this.
So what happens is that when we are stopping tasks we wait for them to finish, that includes flushing any logs that have not been sent over the handler channel yet. Because nothing is reading from that channel when we are performing this update we get stuck waiting there indefinitely.
To fix this we need to keep on reading while we perform the update and stop that when we are done
Which issue(s) this PR fixes
fixes: #3456
fixes: #3472
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PR Checklist