Uploaded image for project: 'Core Server'
  1. Core Server
  2. SERVER-40250

High contention for ReplicationCoordinatorImpl::_mutex in w:majority workloads

    XMLWordPrintable

Details

    • Bug
    • Status: Closed
    • Major - P3
    • Resolution: Duplicate
    • None
    • None
    • Replication
    • ALL

    Description

      bartle reports high contention for the replication coordinator mutex in heavy insert workloads with w:majority writes, which leads to low CPU utilization and bottlenecking on a synthetic resource (the mutex). This is problematic on deployments with many cores, but can even be a problem on 16-core machines, as he mentions in a comment on another ticket.

      Shortening the critical section under the mutex in setMyLastAppliedOpTimeForward and particularly in _wakeReadyWaiters_inlock is one possible approach to mitigating the problem. Finer grained locking around waiters might be another.

      Attachments

        Issue Links

          Activity

            People

              backlog-server-repl Backlog - Replication Team
              schwerin@mongodb.com Andy Schwerin
              Votes:
              0 Vote for this issue
              Watchers:
              23 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved: