Steve Hillman wrote: > I realize that this topic has been fairly well beaten to death on this forum, > but I've also read numerous comments from ZFS developers that they'd like to > hear about significantly different performance numbers of ZFS vs UFS for > NFS-exported filesystems, so here's one more. > > The server is an x4500 with 44 drives configured in a RAID10 zpool, and two > drives mirrored and formatted with UFS for the boot device. It's running > Solaris 10u4, patched with the Recommended Patch Set from late Dec/07. The > client (if it matters) is an older V20z w/ Solaris 10 3/05. No tuning has > been done on either box > > The test involved copying lots of small files (2-10k) from an NFS client to a > mounted NFS volume. A simple 'cp' was done, both with 1 thread and 4 parallel > threads (to different directories) and then I monitored to see how fast the > files were accumulating on the server. > > ZFS: > 1 thread - 25 files/second; 4 threads - 25 files/second (~6 per thread) > > UFS: (same server, just exported /var from the boot volume) > 1 thread - 200 files/second; 4 threads - 520 files/second (~130/thread)
With this big a difference, I suspect the write cache is enabled on the disks. UFS requires this cache to be disabled or battery backed otherwise corruption can occur. > > For comparison, the same test was done to a NetApp FAS270 that the x4500 was > bought to replace: > 1 thread - 70 files/second; 4 threads - ~250 files/second I don't know enough about that system but perhaps it has NVRAM or an SSD to service the synchronous demands of NFS. An equivalent setup could be configured with a separate intent log on a similar fast device. > > I have been able to work around this performance hole by exporting multiple > ZFS filesystems, because the workload is spread across a hashed directory > structure. I then get 25 files per FS per second. Still, I thought I'd raise > it here anyway. If there's something I'm doing wrong, I'd love to hear about > it. > > I'm also assuming that this ties into BugID 6535160 "Lock contention on > zl_lock from zil_commit", so if that's the case, please add another vote for > making this fix available as a patch for S10u4 users I believe this is a different problem than 6535160. > > Thanks, > Steve Hillman > > > This message posted from opensolaris.org > _______________________________________________ > 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
