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Home -> Community -> Usenet -> c.d.o.server -> Re: DB_FILE_MULTIBLOCK_READ_COUNT question
Solaris uses either 4K or 8K blocks depending on the hardware. It does
allocation on a 512 byte basis but reads and writes 4k or 8K each time. Check
out
http://www.sunworld.com/sunworldonline/swol-05-1999/swol-05-filesystem-3.html
for more details.
Cheers John G
In message <8q62i0Mon, 18 Sep 2000 16:44:32 -0500m2$1_at_news.sinet.slb.com>,
"Yong Huang" <yhuang_at_indigopool.com> wrote:
>
> Determine the block size like this:
>
> lurch% mkdir aaa
> lurch% ls -ld aaa
> drwxr-xr-x 2 oracle8 oinstall 512 Sep 18 14:35 aaa
>
> So it's 512 bytes. The benefit of a small size is better disk space usage.
> I'm sure there're other benefits.
>
> Yong Huang
> yhuang_at_indigopool.com
>
>
> Michael J. Moore <hicamel_at_home.com> wrote in message
> news:d5Bw5.206744$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 Wed Sep 20 2000 - 00:00:00 CDT