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Re: DB_FILE_MULTIBLOCK_READ_COUNT question

From: Michael J. Moore <mNiOcShPaAeMl.j.moore_at_wcom.com>
Date: Tue, 19 Sep 2000 17:55:02 GMT
Message-ID: <WLNx5.22$6f.947@pm02news.wcom.com>

Okay so 512 is my blocksize, but how do I determine my "system buffer size" ?

thanks,
Mike

"Yong Huang" <yhuang_at_indigopool.com> wrote in message news:8q62i0$dm2$1_at_news.sinet.slb.com...
> Determine the block size like this:
>
> lurch% mkdir aaa
> lurch% ls -ld aaa
> drwxr-xr-x 2 oracle8 oinstall 512 Sep 18 14:35 aaa
>
> So it's 512 bytes. The benefit of a small size is better disk space usage.
> I'm sure there're other benefits.
>
> Yong Huang
> yhuang_at_indigopool.com
>
>
> Michael J. Moore <hicamel_at_home.com> wrote in message
> news:d5Bw5.206744$i5.2882893_at_news1.frmt1.sfba.home.com...
> > Okay, thanks Dave. I guess I will have to learn a little bit about
 Solaris.
> > It is a bit disapointing to hear my block size is probably only 512, I
 don't
> > want to believe it.
> > thanks for your help :-)
> > mike
> >
> > "Dave A" <dave_and_vanna_at_hotmail.com> wrote in message
> > news:ss5adcqvh3t60_at_corp.supernews.com...
> > > The OS block size is more than likely 512b on your Solaris machine,
 not
> > > 8192b. The Oracle block size is usually set to a multiple of the OS
 block
> > > size. Most production databases on Solaris will use an 8192 oracle
 block
> > > size, some will use larger, few will use less.
> > >
> > > I *want* to say your I/O block size is 32k or 64k, but I do not know
 how
 to
> > > determine that on Solaris (I'd ask the SA:-)
> > >
> > > Anyway, what the DBA Handbook was explaining is that the
> > > multi_block_read_count parameter can't be set to 100 or something like
 that
> > > as the OS is limited to reading I/O block / Oracle block.
> > >
> > >
> > > --
> > > Dave A
> > >
> > >
> > > "Michael J. Moore" <mNiOcShPaAeMl.j.moore_at_wcom.com> wrote in message
> > > news:OVww5.1156$6a1.19316_at_pm01news.wcom.com...
> > > > In the Oracle 8i DBA Handbook I am reading on page 335.:
> > > >
> > > > "The number of blocks read at a time is limited by the I/O buffer
 size
 of
> > > > your operating system."
> > > >
> > > > The DB_BLOCKSIZE paramater in the init.ora is 8192 which means that
 the
 OS
> > > > has an 8k disk block size (assuming that the DBA who set the
 parameter
 knew
> > > > the disk block size and set a 1 to 1 ratio).
> > > >
> > > > But, what is the I/O buffer size of my OS. I am running Solaris on a
 Sun
> > > > Enterprise II. Is there a command that I can type that will tell me
 what
 the
> > > > I/O block size is?
> > > >
> > > > thanks,
> > > > Mike
> > > >
> > >
> > >
> >
> >
>
>
  Received on Tue Sep 19 2000 - 12:55:02 CDT

Original text of this message

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