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  1. Core Server
  2. SERVER-4243

If there is a pending write due to an fsync lock, all reads are blocked

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    • Type: Icon: Bug Bug
    • Resolution: Done
    • Priority: Icon: Minor - P4 Minor - P4
    • 2.2.0
    • Affects Version/s: 2.0.1
    • Component/s: Concurrency
    • Labels:
      None
    • Environment:
      64bit Ubuntu 11.04 + gcc 4.5.2
    • Linux

      By locking the database and issuing a single write, all readers are starved. No read operations can go through.

      Because of this, a new shell will start but cannot be used – it must be doing some read-lock requiring operation. Ostensibly, this is due to the shell attempting to read but being unable to do so due to the waiting write starving any reader attempt.

      Issuing "mongo --eval 'db.fsyncUnlock()'" will unlock the database, allow writes through, and unfreeze the shell.

            Assignee:
            dwight@mongodb.com Dwight Merriman
            Reporter:
            dan@mongodb.com Daniel Pasette (Inactive)
            Votes:
            3 Vote for this issue
            Watchers:
            11 Start watching this issue

              Created:
              Updated:
              Resolved: