On Oct 28, 2013, at 11:16 AM, Slawa Olhovchenkov wrote: > On Mon, Oct 28, 2013 at 10:45:02AM -0700, aurfalien wrote: > >> >> On Oct 28, 2013, at 2:28 AM, Slawa Olhovchenkov wrote: >> >>> I can be wrong. >>> As I see ZFS cretate seperate thread for earch txg writing. >>> Also for writing to L2ARC. >>> As result -- up to several thousands threads created and destoyed per >>> second. And hundreds thousands page allocations, zeroing, maping >>> unmaping and freeing per seconds. Very high overhead. >>> >>> In systat -vmstat I see totfr up to 600000, prcfr up to 200000. >>> >>> Estimated overhead -- 30% of system time. >>> >>> Can anybody implement thread and page pool for txg? >> >> Would lowering vfs.zfs.txg.timeout be a way to tame or mitigate this? > > vfs.zfs.txg.timeout: 5 > > Only x5 lowering (less in real case with burst writing). And more fragmentation on writing and etc. So leave it default in other words. Good to know. - aurfReceived on Mon Oct 28 2013 - 17:25:27 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:40:43 UTC