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  1. Core Server
  2. SERVER-9596

Change debug message "we think data is in ram" to a counter

    • Type: Icon: Improvement Improvement
    • Resolution: Won't Fix
    • Priority: Icon: Minor - P4 Minor - P4
    • None
    • Affects Version/s: 2.4.3
    • Component/s: None
    • None
    • Environment:
      All, but especially on Windows

      Debug builds of mongod check to see if our internal working set tracking is accurate, and display the message "warning: we think data is in ram but system says no" when our tracking code thinks that data is in RAM but the operating system's authoritative answer is that the data is not in RAM.

      We use 'QueryWorkingSetEx()' on Windows and 'mincore()' on other OSes to see if a particular page is in RAM.

      On Windows, the QueryWorkingSetEx API doesn't actually tell us what is in RAM; it tells us what is in RAM and on the "Working Set" list. Pages that are in RAM and are on the 'Standby' list are not reported by this API. The result is that Windows debug builds spew large quantities of useless output, making logs hard to use.

      These events should be tracked in a counter and not logged.

            Assignee:
            tad Tad Marshall
            Reporter:
            tad Tad Marshall
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              Created:
              Updated:
              Resolved: