On 08/24/2012 12:25 PM, Julius Roberts wrote: > On 24 August 2012 15:03, Robbie Crash <sardonic.smi...@gmail.com> wrote: >> Are you using compression or dedup on the FS? > > Yes, both. We're getting about 1.5x dedup on the Backups pool,
So let me get this straight, you've got a 2TB dataset with dedup and compression on a machine with 1GB of RAM and you're complaining about poor performance? This is *expected* behavior. Your DDT simply doesn't fit into RAM, so the machine has to go and fetch entries on practically every write to the pool, so your pool is going to get hit hard by random-read loads as the kernel has to re-read portions of the DDT while doing dedup. See http://constantin.glez.de/blog/2011/07/zfs-dedupe-or-not-dedupe for a guide on RAM sizing when doing dedup. > not sure how to calculate compression # zfs get compressratio <dataset> Cheers, -- Saso _______________________________________________ OpenIndiana-discuss mailing list OpenIndiana-discuss@openindiana.org http://openindiana.org/mailman/listinfo/openindiana-discuss
