On Thu, 2007-08-30 at 13:07 -0700, eric kustarz wrote: > On Aug 30, 2007, at 12:33 PM, Jeffrey W. Baker wrote: > > > > Uh, whoops. As I freely admit this is my first encounter with > > opensolaris, I just built the software on the assumption that it would > > be 64-bit by default. But it looks like all my benchmarks were built > > 32-bit. Yow. I'd better redo them with -m64, eh? > > > > [time passes] > > > > Well, results are _substantially_ worse with bonnie++ recompiled at > > 64-bit. Way, way worse. 54MB/s linear reads, 23MB/s linear writes, > > 33MB/s mixed. > > Hmm, what are you parameters?
bonnie++ -g daemon -d /tank/bench/ -f This becomes more interesting. The very slow numbers above were on an aged (post-benchmark) filesystem. After destroying and recreating the zpool, the numbers are similar to the originals (55/87/37). Does ZFS really age that quickly? I think I need to do more investigating here. > >> For the randomio test, it looks like you used an io_size of 4KB. Are > >> those aligned? random? How big is the '/dev/sdb' file? > > > > Randomio does aligned reads and writes. I'm not sure what you mean > > by /dev/sdb? The file upon which randomio operates is 4GiB. > Another thing to know about ZFS is that it has a variable block size > (that maxes out at 128KB). And since ZFS is COW, we can grow the > block size on demand. For instance, if you just create a small file, > say 1B, you're block size is 512B. If you go over to 513B, we double > you to 1KB, etc. # zfs set recordsize=2K tank/bench # randomio bigfile 10 .25 .01 2048 60 1 total | read: latency (ms) | write: latency (ms) iops | iops min avg max sdev | iops min avg max sdev --------+-----------------------------------+---------------------------------- 463.9 | 346.8 0.0 21.6 761.9 33.7 | 117.1 0.0 21.3 883.9 33.5 Roughly the same as when the RS was 128K. But, if I set the RS to 2K before creating bigfile: total | read: latency (ms) | write: latency (ms) iops | iops min avg max sdev | iops min avg max sdev --------+-----------------------------------+---------------------------------- 614.7 | 460.4 0.0 18.5 249.3 14.2 | 154.4 0.0 9.6 989.0 27.6 Much better! Yay! So I assume you would always set RS=8K when using PostgreSQL, etc? -jwb _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
