Re: 9i multi cache buffer

Jonathan Lewis wrote:
>
> It was more of a hypothetical question than an
> absolute need for information. And Nuno's comment
> on this issue was also relevant - different machines
> have difference memory page sizes, and can optimise
> some actions based on memory paging.
>
> Many years ago, an HP specialist pointed out to me
> that the HP had a default memory page size of 4K,
> and suggested that it's filesystem handling could therefore
> be affected by choosing a 4K block filesystem rather than
> an 8K filesystem. It isn't the sort of thing you can test
> realistically, unfortunately - in principle it sounds correct,
> and in principle it sounds as if you just set up lots of
> different file systems for lots of different Oracle block sizes.
>
> This means, of course, that I have to disagree with (at
> least) some of your response to Geoff Ingram - there are
> arguments for choosing to maintain different block sizes
> in the databases that do not relate to the speed of the
> file system, and even if the file-system interferes in some
> way, there are still cases where other considerations can
> be more important. However, I suspect that many of those
> arguments will never be subject to a strict test.
>
> --
> Regards
>
> Jonathan Lewis
> http://www.jlcomp.demon.co.uk
>
> Next Seminar dates:
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>
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>
> Howard J. Rogers wrote in message
> <7JhA9.75556$g9.212743_at_newsfeeds.bigpond.com>...
> >You're asking me????
> >
> >My advice on such matters is (1) consult your vendor and (2) consult
> Steve
> >Adams, who says that HP-UX has an 8K block size. He goes on to say
> the
> >following (which makes about as much sense to me as the output from
> top):
> >
> >If your operating system is not listed in the table above, you should
> be
> >able to work out the file system buffer size by studying the ratio of
> blks/s
> >to r+w/s in the sar -d output for various buffered filesystems.
> >
> >Let us know what the outcome is, so I can shut up about a 'right'
> block
> >size.
> >
> >Regards
> >HJR
> >

Happiness is a raw "file system"

:-)

-- 
==============================
Connor McDonald

http://www.oracledba.co.uk

"Some days you're the pigeon, some days you're the statue..."