Re: Database Block Size

Hi Frank,

On the issue of raw, have a look at the whitepapers on the Veritas web site. They consistently claim to get "near raw disk performance", except that they can claim to exceed raw disk performance when using Cached Quick I/O on large memory systems running 32-bit Oracle. In other words, unless you are totally incompetent in sizing your memory allocations, raw will outperform the expensive Veritas solutions marginally, and may outperform their standard solutions dramatically if your I/O workload is heavy. See their white paper "VERITAS Database Edition 2.1 for Oracle - Performance Brief – OLTP Comparison on Solaris 7" at http://eval.veritas.com/webfiles/docs/dbed_2-1_perf.pdf for more details.

@   Regards,
@   Steve Adams
@   http://www.ixora.com.au/
@   http://www.christianity.net.au/

-----Original Message-----
From: "Frank" <frankbo_at_interaccess.nl>

I'm convinced. And willing to learn. And -rereading the thread in Unix modeit  makes more sense. Or the opposite <grin> Will go for 8k on Unix as from now on. Cooked, that is. BTW, I come across many (well...) sysops that are _very_ reluctant to start off with raw fs. Cannot convince them always. Any war stories on terrible performing dbms's on cooked fs, that flash on raw?

--
Frank
Howard J. Rogers <howardjr_at_www.com> schreef in berichtnieuws
39ec3a53_at_news.iprimus.com.au...
> "frank" <fbortel_at_home.nl> wrote in message
 news:39EB3CD5.F8F83116_at_home.nl...


> > Comment inline

> >

> > "Howard J. Rogers" wrote:

> >

> > > Comments below

> > > HJR

> > > --

> >

>
> --------------------------------------------------------------------------


> > > Opinions expressed are my own, and not those of Oracle Corporation

> > > Oracle DBA Resources:

 http://www.geocities.com/howardjr2000


> >

>
> --------------------------------------------------------------------------


> >

> > > <snip>

> > > That's got to be one of the most sensible postings of the subject I've

 seen


> > > for weeks.  All of it makes sense with (forgive me) the one exception

 of


> > > rather avoiding the discussion about block size.  I keep seeing total

 cr*p


> > > posted here about the "fact" that block size would seem to depend on

 what


> > > you use the database for: OLTP allegedly requires a small block size,

 and


> > > data warehousing doesn't.

> >

> > Maybe you could tell Oracle to alter the documentation, then? You're

 closer


> > than me ;-)

> >

>
> Have you read the documentation for the Backup and Recovery course???  The
> DBA course is bad enough, but the BUR one is worse.  And no, complaining
> about it doesn't make a bit of difference.  So whatever the documentation
> says, talk to the experts, and Steve Adams knows what he's talking about
 it
> (as far as I'm concerned, anyway).
>
> And he says 8K is a given for most Unixes with file systems, for reasons
> that make entire good sense as far as I can work out.
>
> So take it up with him.
>
> Personally, I reckon this subject arouses so much debate because there are
> so many DBAs out there who made the wrong decision, and don't like to
 admit
> it.  Probably too much effort to fix the balls-up.
>
> Regards
> HJR
>
>
>
>
>
>