Looking for some AIX discussion regarding AIO, CIO, database options, filesystem mount options

From: joshuasingham <joshuasingham_at_gmail.com>
Date: Fri, 2 Nov 2012 22:23:39 +0800
Message-ID: <CAKYyGsFinj-6tNwP3Lb53drFtVbN2uPWKZitchZK-FbaEHN_pg_at_mail.gmail.com>

Hi Chris,
From my previous experience with aix and jfs2 I found the best performance come when filesystem_options=setall with the cio mount combo and also enabling large page for the sga memory helps with performance overall, also make sure the aix vmm parameters are set properly



On Nov 2, 2012 9:21 PM, <Christopher.Taylor2_at_parallon.net> wrote:

> Folks,
> I'm new to AIX and I'm a bit confused on the configuration options for
> filesystems regarding the use of aio, cio.
> I've been through multiple metalink docs and publib.ibm.com docs but I
> still feel like I'm missing a key piece of the puzzle.
> (I'm not looking for an "answer", I'm looking for how to dig into this -
> what to look for and how to connect "the dots" so to speak)
> Here's what I have 'inherited' and below that, what I'm seeing. Looking
> for someone with AIX experience to share some ideas/thoughts/suggestions.
> Server:
> AIX 6.1.0
> System Model: IBM,9117-MMA
> Machine Serial Number: 0699500
> Processor Type: PowerPC_POWER6
> Processor Implementation Mode: POWER 6
> Processor Version: PV_6_Compat
> Number Of Processors: 4
> Processor Clock Speed: 4208 MHz
> CPU Type: 64-bit
> Kernel Type: 64-bit
> Memory Size: 24576 MB
> Good Memory Size: 24576 MB
> Platform Firmware level: EM350_038
> Firmware Version: IBM,EM350_038
> Storage:
> A bunch of "EMC Symmetrix FCP VRAID" devices
> Storage mount options: jfs2 rw,cio,log=INLINE
> Database:
> "filesystemio_options"=async
> db_writer_processes=1
> It appears our WRITES are slow but reads seem to be okay which makes me
> think of a misconfiguration in the IO somewhere. I need to boost my IO
> throughput here (I think) and I think I have a mismatch somewhere regarding
> database configuration and filesystem configuration.
> On my AWR reports I'm seeing:
> https://gist.github.com/4001326
> Also, someone told me in passing that AIX had a hard time reading &
> writing (simultaneously) to the same filesystem based on some AIX
> parameters that could be adjusted? Does that ring a bell with anyone?
> Chris Taylor
> Oracle DBA
> Parallon IT&S
> christopher.taylor2_at_parallon.net<mailto:christopher.taylor2_at_parallon.net>
> www.parallon.net
> --
> http://www.freelists.org/webpage/oracle-l

Received on Fri Nov 02 2012 - 15:23:39 CET

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