Hello Neil, Thursday, September 27, 2007, 11:40:42 PM, you wrote:
NP> Roch - PAE wrote: >> Pawel Jakub Dawidek writes: >> > I'm CCing zfs-discuss@opensolaris.org, as this doesn't look like >> > FreeBSD-specific problem. >> > >> > It looks there is a problem with block allocation(?) when we are near >> > quota limit. tank/foo dataset has quota set to 10m: >> > >> > Without quota: >> > >> > FreeBSD: >> > # dd if=/dev/zero of=/tank/test bs=512 count=20480 >> > time: 0.7s >> > >> > Solaris: >> > # dd if=/dev/zero of=/tank/test bs=512 count=20480 >> > time: 4.5s >> > >> > With quota: >> > >> > FreeBSD: >> > # dd if=/dev/zero of=/tank/foo/test bs=512 count=20480 >> > dd: /tank/foo/test: Disc quota exceeded >> > time: 306.5s >> > >> > Solaris: >> > # dd if=/dev/zero of=/tank/foo/test bs=512 count=20480 >> > write: Disc quota exceeded >> > time: 602.7s >> > >> > CPU is almost entirely idle, but disk activity seems to be high. >> > >> >> >> Yes, as we are near quota limit, each transaction group >> will accept a small amount as to not overshoot the limit. >> >> I don't know if we have the optimal strategy yet. >> >> -r NP> Aside from the quota perf issue, has any analysis been done as to NP> why FreeBSD is over 6X faster than Solaris without quotas? NP> Do other perf tests show a similar disparity? NP> Is there a difference in dd itself? NP> I assume that it was identical hardware and pool config. Good question. It should have been cached on Solaris so it should definitely be below 1s range. -- Best regards, Robert mailto:[EMAIL PROTECTED] http://milek.blogspot.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
