On 3/30/2010 2:44 PM, Adam Leventhal wrote: > Hey Karsten, > > Very interesting data. Your test is inherently single-threaded so I'm not > surprised that the benefits aren't more impressive -- the flash modules on > the F20 card are optimized more for concurrent IOPS than single-threaded > latency. > >
Yes it would be interesting to see the Avg numbers for 10 or more clients (or jobs on one client) all performing that same test. -Kyle > Adam > > On Mar 30, 2010, at 3:30 AM, Karsten Weiss wrote: > > >> Hi, I did some tests on a Sun Fire x4540 with an external J4500 array >> (connected via two >> HBA ports). I.e. there are 96 disks in total configured as seven 12-disk >> raidz2 vdevs >> (plus system, spares, unused disks) providing a ~ 63 TB pool with fletcher4 >> checksums. >> The system was recently equipped with a Sun Flash Accelerator F20 with 4 FMod >> modules to be used as log devices (ZIL). I was using the latest snv_134 >> software release. >> >> Here are some first performance numbers for the extraction of an >> uncompressed 50 MB >> tarball on a Linux (CentOS 5.4 x86_64) NFS-client which mounted the test >> filesystem >> (no compression or dedup) via NFSv3 (rsize=wsize=32k,sync,tcp,hard). >> >> standard ZIL: 7m40s (ZFS default) >> 1x SSD ZIL: 4m07s (Flash Accelerator F20) >> 2x SSD ZIL: 2m42s (Flash Accelerator F20) >> 2x SSD mirrored ZIL: 3m59s (Flash Accelerator F20) >> 3x SSD ZIL: 2m47s (Flash Accelerator F20) >> 4x SSD ZIL: 2m57s (Flash Accelerator F20) >> disabled ZIL: 0m15s >> (local extraction 0m0.269s) >> >> I was not so much interested in the absolute numbers but rather in the >> relative >> performance differences between the standard ZIL, the SSD ZIL and the >> disabled >> ZIL cases. >> >> Any opinions on the results? I wish the SSD ZIL performance was closer to the >> disabled ZIL case than it is right now. >> >> ATM I tend to use two F20 FMods for the log and the two other FMods as L2ARC >> cache >> devices (although the system has lots of system memory i.e. the L2ARC is not >> really >> necessary). But the speedup of disabling the ZIL altogether is appealing >> (and would >> probably be acceptable in this environment). >> -- >> This message posted from opensolaris.org >> _______________________________________________ >> zfs-discuss mailing list >> zfs-discuss@opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss >> > > -- > Adam Leventhal, Fishworks http://blogs.sun.com/ahl > > _______________________________________________ > 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
