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  1. WiredTiger
  2. WT-1857

Reduce allocation overhead in cache when idle

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    • Type: Icon: Task Task
    • Resolution: Won't Fix
    • Priority: Icon: Major - P3 Major - P3
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      There are cases where WiredTiger will maintain many pages in cache for a clean tree. Those pages may contain empty update and modify structures.

      It would be good if we could have a "maintenance" mode for eviction (or possibly the sweep server) that looks for such pages, even when the cache isn't full, and rewrites the in-memory version to be clean.

      The motivation for the change is that there is overhead in memory allocators. WiredTiger tends to allocate many small chunks of memory. With a large cache (10s of GB), the time to free those structures (even if there is nothing to reconcile) can be high.

      Related to MongoDB JIRA issue SERVER-17907

            Assignee:
            keith.bostic@mongodb.com Keith Bostic (Inactive)
            Reporter:
            alexander.gorrod@mongodb.com Alexander Gorrod
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