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  1. Couchbase Server
  2. MB-37468

Race between ActiveStream next and completeBackfill preventing sending of StreamEnd or state transition

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Details

    • Bug
    • Resolution: Fixed
    • Major
    • 6.0.4, 6.5.1
    • 5.5.0, 5.5.1, 5.5.2, 5.5.3, 5.5.4, 5.5.5, 5.5.6, 6.0.0, 6.0.1, 6.0.2, 6.0.3, 6.5.0
    • couchbase-bucket
    • None
    • Triaged
    • No

    Description

      Identified a race condition between ActiveStream::next and ActiveStream::completeBackfill where we do not notify the stream due to itemsReady being true when completing a backfill, but a racing producer stepping can find no items in the readyQ and remove the Stream from the producers ready queue. This causes us to send all items from a disk backfill but not a stream end. Unsure if this affects versions prior to 5.5 branch.

      This can also manifest in a backfill failing to transition state to either InMemory or TakeoverSend which affects replication too.

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          relates to

          Bug - A problem which impairs or prevents the functions of the product. MB-54591 Lost wakeup in ActiveStream can result in DCP clients not receiving seqnos until another mutation occurs

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed
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              ben.huddleston Ben Huddleston
              ben.huddleston Ben Huddleston
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              Dates

                Created:
                Updated:
                Resolved:

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