RE: Async I/O config/tuning on Linux

From: Herring Dave - dherri <>
Date: Thu, 24 Jul 2008 13:55:49 -0500
Message-ID: <>


We have pretty much the same (, 64bit, RHEL AS4). We have aio-max-nr set to 3145728 and aio-nr at 74752. We're waiting on approval to apply the same patch, to resolve the same problem. Not sure if this helps.


Dave Herring, DBA | A c x i o m M I C S / C S O

630-944-4762 office | 630-430-5988 wireless | 630-944-4989 fax

-----Original Message-----
[] On Behalf Of Hemant K Chitale Sent: Thursday, July 24, 2008 10:26 AM
Subject: Async I/O config/tuning on Linux


I/O RESOURCES (1) " messages in a test environment (, 64bit, 
RHEL AS4) where we are testing Async IO Patch #6836997  .  This patch 
contains the fix for Bug#6087207 and other Async IO bugs.
We are also considering applying the Patch for Bug#6656824 (DBWR crashes after one-off fix for 6087207).

However, what Linux parameters should also be tuned ? aio-max-size doesn't exist in RHEL 4 . What values should "aio-max-nr" and
"aio-nr" be configured for ?

Hemant K Chitale

"A 'No' uttered from the deepest conviction is better than a 'Yes'
merely uttered to please, or worse, to avoid trouble." Mohandas Gandhi Quotes


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Received on Thu Jul 24 2008 - 13:55:49 CDT

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