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  1. Core Server
  2. SERVER-37988

recover locks on step up at the beginning of the state transition rather than at the end

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Details

    • Task
    • Status: Closed
    • Minor - P4
    • Resolution: Fixed
    • None
    • 4.1.12
    • Replication
    • Fully Compatible
    • Storage NYC 2019-05-06, Storage NYC 2019-05-20

    Description

      Prepared transactions hold collection and database IX locks across state transitions, and can only release those locks by processing a 'commitTransaction' or 'abortTransaction' command. It is very possible that in order to receive a 'commitTransaction' or 'abortTransaction' command, a node must go through a state transition to step up or down. Thus we cannot just wait for the prepared transaction to release its locks to acquire locks for the state transition.

      This means that state transitions cannot acquire locks that would conflict with locks held by a prepared transaction.

      The only state transition that I know of that acquires locks is step-up.

      Shutdown does not count as a state transition. It aborts all prepared storage transactions without making that abort durable in any way before acquiring any locks. This occurs after shutting down the replication system (though before killing all operations), so I think it should be safe.

      Attachments

        Issue Links

          depends on

          Task - A task that needs to be done. SERVER-37987 Use finer grained locks for on step up reads and writes

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

          Task - A task that needs to be done. SERVER-38139 Ban temporary collections in prepared transactions

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

          Task - A task that needs to be done. SERVER-38140 Only acquire a Database IX lock for replicated collection drops

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

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-39520 Only use collection MODE_X locks for collection drops

          • Major - P3 - Major loss of function.
          • Closed
          is related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-35365 MapReduce temporary inc collections should be written to the local database

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

          Task - A task that needs to be done. SERVER-37199 Yield locks of transactions in secondary application

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

          Task - A task that needs to be done. SERVER-41037 Stepup should kill all user operations(that encounters prepare conflict) before taking RSTL lock in X.

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

          Bug - A problem which impairs or prevents the functions of the product. SERVER-40700 Deadlock between read prepare conflicts and state transitions

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

          Bug - A problem which impairs or prevents the functions of the product. SERVER-40723 Deadlock between S lock acquisition on secondary and prepare conflict

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

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-37381 Allow prepared transactions to survive state transitions

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

          Activity

            People

              gregory.wlodarek@mongodb.com Gregory Wlodarek
              judah.schvimer@mongodb.com Judah Schvimer
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              Dates

                Created:
                Updated:
                Resolved: