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  1. Core Server
  2. SERVER-4740

Use monotonic clock sources for Timer

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    • Service Arch

    Description

      Mongo currently uses gettimeofday() for all posix interval metrics. As this function is not monotonic, we may see anomalies under certain conditions; e.g. VMM live migration, some SMP process migrations, system sleep/suspend/hibernate, NTP or system date changes, TSC-related kernel or VMM bugs, etc.

      The FineClock class (src/mongo/db/stats/fine_clock.h) implements a monotonic clock source, however the code is currently Linux specific and unused. The goal here would be to make this class fully functional on all platforms and ensure performance is >= gettimeofday(). It may also be worth migrating the win32 code from boost::xtime to QueryPerformanceCounter() or similar as boost::xtime has been deprecated.

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          is duplicated by

          Bug - A problem which impairs or prevents the functions of the product. SERVER-6444 when time (ticks) go backwards Timer overflows

          • Major - P3 - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. SERVER-6550 db.currentOp() incorrectly reports insert secs_running as 1271310

          • Major - P3 - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. SERVER-2886 Many commands being executed for 1271310319ms, mongo

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. SERVER-10603 Absurd query times in log

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. SERVER-4924 Use CLOCK_MONOTONIC for timing rather than gettimeofday

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Closed
          is related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-15122 Result of gettimeofday() is not checked

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Closed
          related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-6452 Replace time(0) calls

          • Major - P3 - Major loss of function.
          • Backlog

          Bug - A problem which impairs or prevents the functions of the product. SERVER-16763 mongod terminate due to mongo::DBTryLockTimeoutException during longevity test with wiredTiger

          • Critical - P2 - Crashes, loss of data, severe memory leak.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. SERVER-18562 YCSB load phase (insert only) push 16 core machine to 100 % due to high resoultion timers

          • Critical - P2 - Crashes, loss of data, severe memory leak.
          • Closed

          Question - SERVER-4709 Strange timing of operations reported in logs

          • Major - P3 - Major loss of function.
          • Closed

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              backlog-server-servicearch Backlog - Service Architecture
              benjamin.becker Ben Becker
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                Updated:
                Resolved: