RE: concurrent I/O on aix server

From: Allen, Brandon <>
Date: Wed, 20 Feb 2008 13:03:06 -0700
Message-ID: <04DDF147ED3A0D42B48A48A18D574C450A855AB7@NT15.oneneck.corp>

I've run that exact config with very good results on 2 different production systems, both with 9.2 and 10.2.  

  1. If you run 10g, you don't have to mount the filesytems with the cio option, just use filesystemio_options=setall and Oracle will open its datafiles with the CIO flag, so they can be on a regular filesystem along with other executables and any other files, e.g. the Oracle software, if you want (I prefer to separate them anyway)
  2. Redologs should definitely be on cio, and these are the only files that require a filesystem created with agblksize=512 since that is the size of IOs to the redo logs, otherwise all IO will be buffered if the block sizes aren't aligned
  3. No need to change the block size for the filesystem holding your datafiles, it just has to be a multiple, so your 16k blocks are a multiple of the default 4k jfs2 block size and all is well

There are lots of papers available on this, info in the standard oracle docs and metalink, and even lots of threads in the archives of this oracle-l list. Here's a couple to get you started in case you haven't read these yet: htm#sthref773  


Privileged/Confidential Information may be contained in this message or attachments hereto. Please advise immediately if you or your employer do not consent to Internet email for messages of this kind. Opinions, conclusions and other information in this message that do not relate to the official business of this company shall be understood as neither given nor endorsed by it.

Received on Wed Feb 20 2008 - 14:03:06 CST

Original text of this message