Hi, On Sun, Dec 18, 2011 at 22:00, Fajar A. Nugraha <w...@fajar.net> wrote: > From http://www.solarisinternals.com/wiki/index.php/ZFS_Best_Practices_Guide > (or at least Google's cache of it, since it seems to be inaccessible > now: > > " > Keep pool space under 80% utilization to maintain pool performance. > Currently, pool performance can degrade when a pool is very full and > file systems are updated frequently, such as on a busy mail server. > Full pools might cause a performance penalty, but no other issues. If > the primary workload is immutable files (write once, never remove), > then you can keep a pool in the 95-96% utilization range. Keep in mind > that even with mostly static content in the 95-96% range, write, read, > and resilvering performance might suffer. > " > > I'm guessing that your nearly-full disk, combined with your usage > performance, is the cause of slow down. Try freeing up some space > (e.g. make it about 75% full), just tot be sure.
I'm aware of the guidelines you refer to, and I have had slowdowns before due to the pool being too full, but that was in the 9x% range and the slowdown was in the order of a few percent. At the moment I am slightly above the recommended limit, and the performance is currently between 1/10000 and 1/2000 of what the other pools achieve - i.e. a few hundred kB/s versus 2GB/s on the other pools - surely allocation above 80% cannot carry such extreme penalties?! For the record - the read/write load on the pool is almost exclusively WORM. Best regards Jan _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
