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  1. WiredTiger
  2. WT-3746

Don't busy wait when syncing the log and waiting for writes to complete

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Details

    • Task
    • Status: Closed
    • Major - P3
    • Resolution: Fixed
    • None
    • 3.6.0-rc5, WT3.0.0
    • None
    • None
    • Storage 2017-12-04

    Description

      While looking at FTDC for the insert workload from SERVER-31694, I noticed some interesting WT log statistics. Namely we are force writing the log slot almost as many times as we write a log record. MongoDB uses the in-memory mode for maximal consolidation and performance. There are a number of places where and reasons why we force out the current in-memory log records. We should investigate where these calls are coming from.

      Most of these are effectively a no-op because in attempting to force out the log records we find we can skip it because there are no outstanding records to write.

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        1. logstats.png
          45 kB
          Susan LoVerso

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          People

            sue.loverso@mongodb.com Susan LoVerso
            sue.loverso@mongodb.com Susan LoVerso
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            Dates

              Created:
              Updated:
              Resolved: