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From: Matthias Hoys <matthias.h...@gmail.com>
Newsgroups: comp.databases.oracle.server
Subject: Slower performance after enabling async io on Oracle Linux
Date: Mon, 14 May 2012 02:03:56 -0700 (PDT)
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Hello,

Platform is Oracle Linux 6.2 64-bit with Oracle 11.2.0.3 64-bit.

After enabling async io, I see slower performance for data pump exports, RMAN backups and long-running queries (between 10 and 15% slower).

I enabled async io with:

ALTER SYSTEM SET FILESYSTEMIO_OPTIONS=SETALL SCOPE=SPFILE;
aio-nr is 19052 and aio-max-nr is 1048576. Storage is on iSCSI.

Anyone else with the same experience? Is extra tuning for async io possible on Oracle Linux?

Thanks,
Matthias Hoys