Synchronization fix for aggregate processor and aggregate event handles on groups#6431
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graytaylor0 merged 1 commit intoJan 26, 2026
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…es when attaching events to the aggregate group. There is a possible synchronization issue in the aggregate processor. It currently calls attachToEventAcknowledgementSet on the aggregate group outside of any locks. It is possible that one thread gets this group. Then thread two gets the closes the group. If thread 1 then attaches the event to that group, thread 2 may still reset it. The solution is to move attachToEventAcknowledgementSet into the locks. Signed-off-by: David Venable <dlv@amazon.com>
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san81
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…es when attaching events to the aggregate group. (opensearch-project#6431) There is a possible synchronization issue in the aggregate processor. It currently calls attachToEventAcknowledgementSet on the aggregate group outside of any locks. It is possible that one thread gets this group. Then thread two gets the closes the group. If thread 1 then attaches the event to that group, thread 2 may still reset it. The solution is to move attachToEventAcknowledgementSet into the locks. Signed-off-by: David Venable <dlv@amazon.com>
simonelbaz
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Jan 31, 2026
…es when attaching events to the aggregate group. (opensearch-project#6431) There is a possible synchronization issue in the aggregate processor. It currently calls attachToEventAcknowledgementSet on the aggregate group outside of any locks. It is possible that one thread gets this group. Then thread two gets the closes the group. If thread 1 then attaches the event to that group, thread 2 may still reset it. The solution is to move attachToEventAcknowledgementSet into the locks. Signed-off-by: David Venable <dlv@amazon.com> Signed-off-by: Simon ELBAZ <elbazsimon9@gmail.com>
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Jan 31, 2026
…es when attaching events to the aggregate group. (opensearch-project#6431) There is a possible synchronization issue in the aggregate processor. It currently calls attachToEventAcknowledgementSet on the aggregate group outside of any locks. It is possible that one thread gets this group. Then thread two gets the closes the group. If thread 1 then attaches the event to that group, thread 2 may still reset it. The solution is to move attachToEventAcknowledgementSet into the locks. Signed-off-by: David Venable <dlv@amazon.com>
simonelbaz
pushed a commit
to simonelbaz/data-prepper
that referenced
this pull request
Jan 31, 2026
…es when attaching events to the aggregate group. (opensearch-project#6431) There is a possible synchronization issue in the aggregate processor. It currently calls attachToEventAcknowledgementSet on the aggregate group outside of any locks. It is possible that one thread gets this group. Then thread two gets the closes the group. If thread 1 then attaches the event to that group, thread 2 may still reset it. The solution is to move attachToEventAcknowledgementSet into the locks. Signed-off-by: David Venable <dlv@amazon.com>
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Description
There is a possible synchronization issue in the aggregate processor. It currently calls
attachToEventAcknowledgementSeton the aggregate group outside of any locks.Possible scenario in time order:
AggregateGroupfrom the map. The get from the map is synchronized, but not necessarily what happens afterward.AggregateGroup. This creates a new aggregate event handle for the group going forward.The end result is that we may have two aggregate events for one group. Both are holding the acknowledgement set, but only one will leave the aggregate processor.
The solution is to attach the event within the locks.
Issues Resolved
N/A
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