On Wed, February 10, 2010 16:28, Will Murnane wrote: > On Wed, Feb 10, 2010 at 17:06, Brian E. Imhoff <beimh...@hotmail.com> > wrote: >> I am in the proof-of-concept phase of building a large ZFS/Solaris based >> SAN box, and am experiencing absolutely poor / unusable performance. >> >> I then, Create a zpool, using raidz2, using all 24 drives, 1 as a >> hotspare: >> zpool create tank raidz2 c1t0d0 c1t1d0 [....] c1t22d0 spare c1t23d00 > Create several smaller raidz2 vdevs, and consider adding a log device > and/or cache devices. A single raidz2 vdev has about as many IOs per > second as a single disk, which could really hurt iSCSI performance. > zpool create tank raidz2 c1t0d0 c1t1d0 ... \ > raidz2 c1t5d0 c1t6d0 ... \ > etc > You might try, say, four 5-wide stripes with a spare, a mirrored log > device, and a cache device. More memory wouldn't hurt anything, > either.
That's useful general advice for increasing I/O I think, but he clearly has something other than a "general" problem. Did you read the numbers he gave on his iSCSI performance? That can't be explained just by overly-large RAIDZ groups I don't think. -- David Dyer-Bennet, d...@dd-b.net; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
