Uploaded image for project: 'Core Server'
  1. Core Server
  2. SERVER-71198

Assert that unkillable operations that take X collection locks do not hold the RSTL

    XMLWordPrintableJSON

Details

    • Improvement
    • Status: Backlog
    • Major - P3
    • Resolution: Unresolved
    • None
    • None
    • None
    • None
    • Storage Execution
    • Execution Team 2022-12-12, Execution Team 2022-12-26, Execution Team 2023-01-09

    Description

      The deadlocks described in SERVER-71191 and SERVER-44722 are caused because the following conditions are true, in general

      • An operation is unkillable by stepdown
      • While holding the RSTL in IX mode, an operation takes an X collection lock. If there are any prepared transactions, this blocks.
      • The stepdown thread tries to acquire the X lock, but blocks because of a conflict

      In this situation, the operation that isn't interrupted by stepdown does not make progress. We should add an assertion to our lock helpers that prevent unkillable operations from taking X locks while also holding the RSTL.

      Attachments

        Issue Links

          is related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-78662 Deadlock with index build, step down, prepared transaction, and MODE_IS coll lock

          • Major - P3 - Major loss of function.
          • Closed

          Task - A task that needs to be done. SERVER-73036 Investigate potential deadlock with index builds

          • Major - P3 - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-72898 Investigate if updateShardIdentityConfigString can use MODE_IX lock

          • Major - P3 - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-72897 Investigate unorthodox locking in ReplicationCoordinatorExternalState

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Closed
          related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-44722 3 way deadlock can happen between hybrid index build, prepared transactions and stepdown thread on primary that runs index build via coordinator.

          • Major - P3 - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. SERVER-71191 Deadlock between index build setup, prepared transaction, and stepdown

          • Major - P3 - Major loss of function.
          • Closed

          Task - A task that needs to be done. SERVER-75288 Investigate whether the stepdown killop thread should kill operations that hold the RSTL

          • Major - P3 - Major loss of function.
          • Open

          Activity

            People

              backlog-server-execution Backlog - Storage Execution Team
              louis.williams@mongodb.com Louis Williams
              Votes:
              0 Vote for this issue
              Watchers:
              7 Start watching this issue

              Dates

                Created:
                Updated: