Hi Meg, I believe that the average duration reported is the total amount of time that exceeded the interval divided by the number of syncs that exceeded the interval. Cassandra is not complaining because commit log syncs took 0.66 ms but rather on average 4 commit log syncs 10060 ms.
Cheers, John On Thu, Mar 7, 2019 at 11:33 AM Meg Mara <mm...@digitalriver.com> wrote: > Hello all, > > > > I recently upgraded from C* 3.0.10 to 3.0.16 and have been receiving these > warnings about Commit-Log durations being longer than the configured > interval. I don’t understand what the problem is, why is the system > complaining about such small sync durations? Please advice. > > > > Here are some warnings: > > > > 3:WARN [PERIODIC-COMMIT-LOG-SYNCER] 2019-03-07 13:32:23,785 > NoSpamLogger.java:94 - Out of 2750 commit log syncs over the past 274s with > average duration of 0.66ms, 4 have exceeded the configured commit interval by > an average of 22.50ms > > > > 2:WARN [PERIODIC-COMMIT-LOG-SYNCER] 2019-03-07 13:27:01,214 > NoSpamLogger.java:94 - Out of 1 commit log syncs over the past 0s with > average duration of 113.00ms, 1 have exceeded the configured commit interval > by an average of 13.00ms > > > > > > Node’s cassandra.yaml setting related to Commit-Log: > > > > commit_failure_policy: stop > > commitlog_directory: /cassandra/log > > commitlog_segment_size_in_mb: 32 > > commitlog_sync: periodic > > commitlog_sync_period_in_ms: 10000 > > commitlog_total_space_in_mb: 4096 > > > > Thank you, > > *Meg Mara* > > > > > -- - John