I think, that direct comparation is useless. Raw IO on file should be the same on file system and on raw device, in any good clustered implementation (aside of block size - if you use read/write size much bigger than file system block size, raw will work faster).
But it all changes in real application world - depending on the application, results can be very different. So, it is interesting to compare: - Oracle RAC cluster on raw, on ASM and on OCFS, using the same SAN system; - Oracle standalone database on ext3 FS, OCFSv2 (on single node) and on raw device. - Application such as main system (dont share files but share directories) - Application which dont share directories. ----- Original Message ----- From: "Brian Long" <[EMAIL PROTECTED]> To: "Sunil Mushran" <[EMAIL PROTECTED]> Cc: <[email protected]> Sent: Wednesday, November 15, 2006 9:59 AM Subject: Re: [Ocfs2-users] OCFS2 Block / Clustersize with Oracle 10gR2 > When measuring performance between raw and OCFS2 using Enterprise > Manager and taking half-hour snapshots, are physical reads/writes per > second directly comparable or should we only be looking at "db block > changes", "session logical reads", etc? > > I've got iostat data and graphs of the storage when doing raw and OCFS2 > IO tests. I've also got Enterprise Manager screen shots if they provide > any value. > > Besides switching to Swingbench, how can we verify we are truly getting > the same "IO" between raw and OCFS2 if the physical reads/writes are not > in the same ball-park. > > In fact, when the DBA disabled async IO on the database on OCFS2, the > IO/sec did not decrease at all. > > Thanks for helping. > > /Brian/ > -- > Brian Long | | > IT Infrastructure . | | | . | | | . > Data Center Systems ' ' > Cisco Enterprise Linux C I S C O > > > _______________________________________________ > Ocfs2-users mailing list > [email protected] > http://oss.oracle.com/mailman/listinfo/ocfs2-users > _______________________________________________ Ocfs2-users mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-users
