Tomas Ögren wrote: > On 24 January, 2008 - Steve Hillman sent me these 1,9K bytes: > >> 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) > > To get similar (lower) consistency guarantees, try disabling ZIL.. > google://zil_disable .. This should up the speed, but might cause disk > corruption if the server crashes while a client is writing data.. (just > like with UFS)
Disabling the ZIL does NOT cause disk corruption. It doesn't even cause ZFS to be inconsistent on disk. What it does to is mean that you onlonger have guaranteed synchronous write semantics - ie on crash an application might have done a synch write that never made it to stable storage. BTW there isn't really any such think as "disk corruption" there is "data corruption" :-) -- Darren J Moffat _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
