Re: Performance difference between 2 machines

From: Sybrand Bakker <postbus_at_sybrandb.demon.nl>
Date: Wed, 22 Jun 2005 23:40:07 +0200
Message-ID: <egmjb19qgvlpjjvabgorq8dud7mvkvqffi@4ax.com>

On Wed, 22 Jun 2005 21:19:34 GMT, Fabrizio <fabrizio.magni_at_mycontinent.com> wrote:

>For the "db file scattered read" I'd try to enable (if not already) the
>async i/o (this can make a big difference for batch jobs) and to adjust
>the DB_FILE_MULTIBLOCK_READ_COUNT.

One of the most common problems I see is some 'dba's enable disk_async_io on Unix, even when the file is not on a RAW volume, or on a volume using the proper edition of Veritas. On Solaris it is quite easy to demonstrate in that case all asynchronous calls will fail, after which Oracle reissues the call as an ordinary pread or pwrite.
Depending on the configuration of the OP your advice may have a dentrimental effect.

--
Sybrand Bakker, Senior Oracle DBA

Received on Wed Jun 22 2005 - 16:40:07 CDT