Damian, Are you using compression=on? There was a bug in the past (fixed now) where if compression was turned on, it was being computed by a single thread. The ZFS team fixed the "user data" part of it (i.e user data is compressed in parallel now), but the meta data part is still compressed by one thread. I suspect this might be the issue. One tunable you can try experimenting with is zfs_mdcomp_disable (http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=6485204)
If you can get a kernel stack for this cpu, that would greatly help in identifying the issue. This can be hard, as the thread could migrate :-) hth, -neel On Sun, Aug 19, 2007 at 04:41 PM +1000, Damian Reed - Systems Support Engineer wrote: > Hi All, > > We are currently in the process of testing Solaris 10 with ZFS and > Oracle and are running it on a T2000. > > When checking performance statistics on the T2000, we notice that only > one thread of the CPU appears to be doing any of the processing. > Leaving all other threads seemingly idle. > > Are there any tuning parameters that need to be set or changed when > running Oracle on T2000 using ZFS? Can anyone suggest what I might look > for? > > Any initial suggestions would be greatly appreciated. > > Regards, > > Damian Reed > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
