I would add that you didn't mention what if any optimizations you made with vxfs. Specifically, a default vxfs file system will have a file system block size of 1k, 2k, 4k, or 8k, depending on the file system size. Since you are using Oracle, you should always set the file system block size to 8k, irrelevant of the file systems size, due to Oracle I/O patterns. (You would do this using the vxfs mkfs option "-o bsize=8192").
Also, the "odm" comment that Mike mentions, below, is important, as vxfs is an odm-compliant file system. Before Oracle's odm, people would often use vxfs with it's Quick I/O feature, which enables individual files to be accessed as raw devices directly (again, different in subtle ways from Direct I/O). See the Storage Foundation for Oracle documentation off of Symantec's website. And as Mike mentions, for Oracle RAC, we would probably assume that meant you'd be using multiple Oracle instances on different servers writing to the same shared database, which would imply that you will be using the Clustered Volume Manager (CVM) and Clustered File System (CFS) - which is vxvm and vxfs + the ability to allow concurrent access from multiple hosts (which of course is an additional license, aka $$$). Cheers, Tomer -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mike Gerdts Sent: Monday, 24 November 2008 3:44 AM To: Chris Greer Cc: zfs-discuss@opensolaris.org Subject: Re: [zfs-discuss] Performance bake off vxfs/ufs/zfs need some help On Sat, Nov 22, 2008 at 11:41 AM, Chris Greer <[EMAIL PROTECTED]> wrote: > vxvm with vxfs we achieved 2387 IOPS In this combination you should be using odm, which comes as part of the Storage Foundation for Oracle or Storage Foundation for Oracle RAC products. It makes the database files on vxfs behave much like they live on raw devices and tends to allow much higher transaction rate with fewer physical I/O's and less kernel (%sys) utilization. The concept is similar to but different than direct I/O. This behavior is hard, if not impossible, to test without Oracle in the mix because (AFAIK) oracle is the only thing that knows how to make use of the odm interface. > vxvm with ufs we achieved 4447 IOPS > ufs on disk devices we achieved 4540 IOPS > zfs we achieved 1232 IOPS When you say RAC, I assume you mean multi-instance (clustered) databases. None of those are cluster file systems and as such are worthless for multi-instance oracle databases which require a shared file system. On Linux, you say that you were using ocfs. Where you really using ocfs, or were the databases really in ASM? Oracle's recommendation (last I knew) was to have executables on ocfs and have databases in ASM. Have you tried ASM on Solaris? It should give you a lot of the benefits you would expect from ZFS (pooled storage, incremental backups, (I think) efficient snapshots). It will only work for oracle database files (and indexes, etc.) and should work for clustered storage as well. -- Mike Gerdts http://mgerdts.blogspot.com/ _______________________________________________ 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
