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Sybrand Bakker 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.
Since I'm not sleeping yet...
> 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.
disk_async_io? I was referring to OS aio but since we are here: disk_async_io is enabled by default on 9i (the OP version).
And on a filesystem you need to set FILESYSTEMIO_OPTIONS at, at least, asyncio!
While on linux you have even to relink the binaries!
> 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.
We were discussing of UP-UX and linux here. However solaris as a good kaio (maybe the best available).
Are you referring to a veritas bug? Or solaris one? Which version? Have you contacted support?
> Depending on the configuration of the OP your advice may have a
> dentrimental effect.
>
What's a test case made for?
Nothing better than to test for himself!
-- Fabrizio Magni fabrizio.magni_at_mycontinent.com replace mycontinent with europeReceived on Wed Jun 22 2005 - 17:01:19 CDT