Re: Measuring the impact of Redo Log change
Date: Tue, 9 Sep 2008 10:32:27 +0300
Message-ID: <97b7fd2f0809090032l188c5d62yf756e59652953352@mail.gmail.com>
We have seen significant improvements when we enable CIO option of the JFS2
filesystem where redo logs resides.If you are on JFS2 filesystem, I would
recommend you to have a try with CIO option enable on this filesystem (where
redo logs resides).
Regards,
Jaffar
On Tue, Sep 9, 2008 at 7:32 AM, Deepak Sharma <sharmakdeep_oracle_at_yahoo.com>wrote:
> We recently (today) moved the redo logs from RAID5 to RAID1+0.
>
> The obvious reason of doing this is to make things better in terms of
> performance, as RAID1+0 is better suited for read/writes. Someone pls
> correct me if that's not true.
>
> What are different ways to measure the impact of this change?
>
> The platform is AIX, DB is 10.2.0.3 and DB size is 55TB, and 2TB redo is
> generated each day. There are plans underway to reduce the redo generation
> using direct path etc. (so let's not get diverted by that).
>
> We can try measuring the wait event stats using AWR, session stats etc.,
> but what exactly to look for? 'log file switch completion', 'log file
> sync', are some things that come to mind - what else?
>
> Thanks,
> Deepak
>
>
>
-- Best Regards, Syed Jaffar Hussain Oracle ACE 8i,9i & 10g OCP DBA RAC Certified Expert Official Oracle RAC SIG Representative for Saudi Arabian region ( http://www.oracleracsig.org/) http://jaffardba.blogspot.com/ http://apex.oracle.com/pls/otn/f?p=19297:4:1579866181463918::NO:4:P4_ID:126 ---------------------------------------------------------------------------------- "Winners don't do different things. They do things differently." -- http://www.freelists.org/webpage/oracle-lReceived on Tue Sep 09 2008 - 02:32:27 CDT