Re: performance of redo with CIO option on AIX JFS2 filesystem.

ok.

well, CIO can work well, but as always ...testing is the key. it all depends on what your application does and how it generates IO.

good luck. please post the results of using CIO on datafiles.

regards
anand

On 14/02/06, The Human Fly <sjaffarhussain_at_gmail.com> wrote:
>
> Oracle 9i Rel2. (9205).
> This is bug is not the issue. This was cleared by Oracle support in the
> TAR.
>
> On 2/14/06, Anand Rao <panandrao_at_gmail.com> wrote:
> > Hi,
> >
> > any idea what version of Oracle that you are using :-)
> >
> > thanks for the info...
> >
> > well, there is a lot of debate on 'log file sync' and 'log file parallel
> > write' and there is timing bug too. Look at BUG: 2669566.
> >
> > look at http://www.jlcomp.demon.co.uk/log_file_writes.html
> >
> > also, what was your setting for disk_async_io, filesystemio_options and
> > _lgwr_async_io?
> >
> > did you modify any of these?
> >
> > thanks
> >
> > anand
> >
> >
> > On 14/02/06, The Human Fly <sjaffarhussain_at_gmail.com > wrote:
> > >
> > > Hello list,
> > >
> > > Today we have a light smile on our face because we were struggling
> > > with log file sync event on one of our business critical database. We
> > > opened a TAR and implemented everything they have suggested.
> > > Yesterday, we made litte changes, like, created a new mountpoint
> > > enabling CIO (concurrent I/O) on AIX 5.3 using JFS2 filesystem, and
> > > move our redo groups to this new mount point also increased the size
> > > of redo groups from 512M to 1gb.
> > > When we look at the log file sysn event in the statspack, it was just
> > > vanished. Earlier, we used to get 40% as log file synce in the top
> > > timed events and now it is just 3%. Its really a drastic change in the
> > > wait event.
> > > Now, I am planning to do the same for our datafiles, i.e. enabling cio
> > > and moving the tablespace to new moutn point. Redo has only inserts,
> > > but, for tables, we have read and write, does this can improve the
> > > throughput? Will there be any performance gain? Does anyone using this
> > > kind of option with JFS2 filesystem?
> > >
> > > Thanks for your time.
> > >
> > > --
> > > Best Regards,
> > > Syed Jaffar Hussain
> > > 8i,9i & 10g, OCP DBA
> > > Banque Saudi Fransi,
> > > Saudi Arabia
> > > http://jaffardba.blogspot.com/
> > >
> >
> ----------------------------------------------------------------------------------
> > > "Winners don't do different things. They do things differently."
> > > --
> > > http://www.freelists.org/webpage/oracle-l
> > >
> > >
> > >
> >
> >
>
>
> --
> Best Regards,
> Syed Jaffar Hussain
> 8i,9i & 10g, OCP DBA
> Banque Saudi Fransi,
> Saudi Arabia
> http://jaffardba.blogspot.com/
>
> ----------------------------------------------------------------------------------
> "Winners don't do different things. They do things differently."
>

--
http://www.freelists.org/webpage/oracle-l