Re: The ill effects of NOT using direct I/O
From: Rich Jesse <rjoralist2_at_society.servebeer.com>
Date: Mon, 14 Feb 2011 20:55:48 -0600 (CST)
Message-ID: <85259a6818dc349d4d40ee34f8459823.squirrel_at_society.servebeer.com>
> In 9i you had to enable Direct I/O at filesystem level, this is no longer
> true from 10g. This new behaviour is mentioned in
>
> http://download.oracle.com/docs/cd/B19306_01/server.102/b15658/toc.htm
>
> This is true I believe for AIX, Linux and Tru64.
Date: Mon, 14 Feb 2011 20:55:48 -0600 (CST)
Message-ID: <85259a6818dc349d4d40ee34f8459823.squirrel_at_society.servebeer.com>
> In 9i you had to enable Direct I/O at filesystem level, this is no longer
> true from 10g. This new behaviour is mentioned in
>
> http://download.oracle.com/docs/cd/B19306_01/server.102/b15658/toc.htm
>
> This is true I believe for AIX, Linux and Tru64.
Perhaps, but in AIX it may be worth reading up on Concurrent IO as a replacement for DIO. It has the benefits of DIO without the fun inode locking of JFS2. I believe this would come particularly handy for performance in datafile restores, but I haven't tested it.
The option needs to be applied to the mount options.
Just a thought...
Rich
-- http://www.freelists.org/webpage/oracle-lReceived on Mon Feb 14 2011 - 20:55:48 CST