Re: filesystemio_options option on solaris 9 sparc 64-bit (Oracle 10g)

From my very recent testing, If you set filesystemio_options to setall and you're using UFS it will use direct io. On vxfs it will use AIO. If you set it to directio it will use directio in either filesystem. If you set the direct io filesystem options (mincache and/or convosync) you will be using directio regardless of this parameter. If you link ODM you will be using directio.

1 more thing, when working with LOB's on Solaris having this parameter set to asynch resulted in a lot of fdsync system calls being made which was extremely slow. With the parameter set to setall the fdsync calls went away, but still AIO was being used on Veritas filesystems, but now it was almost as fast as direct IO due to the lack of fdsync calls.

I have an open SR with Oracle/VOS on this subject.

HTH
Finn

On 10/27/07, DBA Deepak <oracle.tutorials_at_gmail.com> wrote:
>
> But is it required to mount the file system with direct_io option? I think
> the parameter takes care of the same. If we mount the file system with
> direct_io option probably we do not need to set the said oracle parameter.
>
> Please correct me if am missing anything.
>
> BTW have not mounted the file system with direct_io option.
>
>
>
>
> On 10/18/07, John Hallas <john.hallas_at_bjss.co.uk> wrote:
> >
> > Have the filesystems been mounted with direct_io option?
> >
> >
> > ------------------------------
> >
> > *From:* oracle-l-bounce_at_freelists.org [mailto:
> > oracle-l-bounce_at_freelists.org] *On Behalf Of *DBA Deepak
> > *Sent:* 17 October 2007 19:39
> > *To:* John Hallas
> > *Cc: *oracle-l
> > *Subject:* Re: filesystemio_options option on solaris 9 sparc 64-bit
> > (Oracle 10g)
> >
> >
> >
> > Hi John,
> >
> >
> > Thanks for your help. In my environment filesystemio_options is set to
> > SETALL
> >
> >
> >
> > Still it is not using directIO as per your test. My server is sparc
> > Solaris 9, 64 bit with Oracle 10.2.0.3.
> >
> >
> >
> > Can you please help me in troubleshooting the same. Am I missing
> > anything?
> >
> >
> >
> > ------------------------------
> >
> > BJSS Limited, 1st Floor Coronet House, Queen Street, Leeds LS1 2TW.
> > Registered in England with company number 2777575.
> > http://www.bjss.co.uk
> >
> >
>
>
> --
> Regards,
>
> Deepak
> Oracle DBA

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