Uploaded image for project: 'Core Server'
  1. Core Server
  2. SERVER-13346

Provide an option to force journal preallocation and recycling

    Details

    • Type: Improvement
    • Status: Open
    • Priority: Minor - P4
    • Resolution: Unresolved
    • Affects Version/s: None
    • Fix Version/s: Backlog
    • Component/s: MMAPv1, Storage
    • Labels:
      None

      Description

      Journal file preallocation and recycling (see preallocj in the code) is enabled based on the outcome of a short performance test run at process start. When mongod is deployed at scale this is likely to result in some servers using preallocj=true and others using preallocj=false. That non-determinism is not good for a DBA.

      I get 10% better throughput from insert benchmark workloads using fast (PCIe flash) storage after forcing preallocj to be true. See http://smalldatum.blogspot.com/2014/03/redo-logs-in-mongodb-and-innodb.html

        Activity

        • Comments
        There are no comments yet on this issue.

          People

          • Votes:
            2 Vote for this issue
            Watchers:
            7 Start watching this issue

            Dates

            • Created:
              Updated: