So to give a little background on this, we have been benchmarking Oracle RAC on Linux vs. Oracle on Solaris. In the Solaris test, we are using vxvm and vxfs. We noticed that the same Oracle TPC benchmark at roughly the same transaction rate was causing twice as many disk I/O's to the backend DMX4-1500.
So we concluded this is pretty much either Oracle is very different in RAC, or our filesystems may be the culprits. This testing is wrapping up (it all gets dismantled Monday), so we took the time to run a simulated disk I/O test with an 8K IO size. vxvm with vxfs we achieved 2387 IOPS vxvm with ufs we achieved 4447 IOPS ufs on disk devices we achieved 4540 IOPS zfs we achieved 1232 IOPS The only zfs tunings we have done are setting set zfs:zfs_nocache=1 in /etc/system and changing the recordsize to be 8K to match the test. I think the files we are using in the test were created before we changed the recordsize, so I deleted them and recreated them and have started the other test...but does anyone have any other ideas? This is my first experience with ZFS with a comercial RAID array and so far it's not that great. For those interested, we are using the iorate command from EMC for the benchmark. For the different test, we have 13 luns presented. Each one is its own volume and filesystem and a singel file on those filesystems. We are running 13 iorate processes in parallel (there is no cpu bottleneck in this either). For zfs, we put all those luns in a pool with no redundancy and created 13 filesystems and still running 13 iorate processes. we are running Solaris 10U6 -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss