Uploaded image for project: 'WiredTiger'
  1. WiredTiger
  2. WT-3938

Reduce memory usage with many tables and sessions

    XMLWordPrintableJSON

Details

    • Improvement
    • Status: Closed
    • Major - P3
    • Resolution: Fixed
    • None
    • 3.6.4, 3.4.14, 3.7.3, WT3.1.0
    • None
    • Storage Non-NYC 2018-03-12
    • v3.6, v3.4, v3.2

    Description

      Prior to MongoDB 3.6 (WT 3.0), WiredTiger used to keep a separate cache in each session of the tables used by that session.

      In workloads with many tables and many sessions, the memory overhead of this per-session table cache can be very large. This was fixed in WT-3476, but that change cannot be backported. Find a simpler approach to reducing the overhead that is possible to backport (e.g., limit the cache to some small number of tables).

      Note that the solution must be tested against the changes for SERVER-33122, which will provide the option to configure how cursors are cached in MongoDB.

      Attachments

        Activity

          People

            michael.cahill@mongodb.com Michael Cahill (Inactive)
            michael.cahill@mongodb.com Michael Cahill (Inactive)
            Votes:
            0 Vote for this issue
            Watchers:
            10 Start watching this issue

            Dates

              Created:
              Updated:
              Resolved: