Re: Moving db to linux
- From: Mladen Gogala <mgogala@xxxxxxxxxxxx>
- To: oracle-l@xxxxxxxxxxxxx
- Date: Wed, 25 Feb 2004 23:07:11 -0500
Oracle supports Ext2 and OCFS, not Ext3. Ext3 has occasional problems
with corruption. As for OCFS, I'll give it a second look it on Saturday,
but it didn't look like it is capable of working without cluster. I should
be capable of linking it into my 2.4.25 kernel. As for async I/O, that is not
a problem. I can always start a bunch of database writers instead of just
one. The problem with direct I/O is that without it, Linux is going to
put each and every block of the database in your buffer cache expanding
it, as necessary to accommodate such big demand. As PC's with infinite RAM
are pretty hard to find, that means that the RAM on your PC will be finite
in quantity and that Linux kernel will start throwing out other things like
samba, network daemons, cupsd, nautilus and gdm to accommodate the increased
demand for networking. Then someone approaches the keyboard and presses
enter or NE key. Linux will page nautilus, gdm, panels and related stuff
right back in, shrinking the buffer pool. Then oracle tries to do transaction,
Linux expands buffer pool....We've got what's known as
"circulus viciosus" or "vicious circle". To the buyers of the IBM equipment
from few decades ago, it is also known as "the spiral of death". The funny
thing is that all that buffering is completely unnecessary because oracle does
its own buffering in SGA, so the Linux buffering is redundant and inefficient.
It does improve BCHR, though, which is of paramount importance, as is well
known on this group.
The only way to avoid costly, and unnecessary double buffering is to make Linux
read and write database files bypassing the buffer cache. That is the very
definition of direct I/O. Now, we're back to square 2.
On 02/25/2004 10:22:09 PM, zhu chao wrote:
> Isn't ext3 good enough? It provide JFS recovery performance and AIO/DIO on
> redhat linux.(On redhat 3, aio seems still have problems, but seems mature
> on 2.1)
>
> Oracle metalink only support ext3/ocfs etc. Seems no jfs support.
>
> Regards
> Zhu Chao.
>
> ----- Original Message -----
> From: "Mladen Gogala" <mladen@xxxxxxxxxxxxxxx>
> To: <oracle-l@xxxxxxxxxxxxx>
> Sent: Thursday, February 26, 2004 3:12 AM
> Subject: Re: Moving db to linux
>
>
> > It should already be in the distribution. Type "rpm -qa|grep jfsutils" and
> > you should get an answer like this:
> > Yogi> rpm -qa|grep jfs
> > jfsutils-1.0.17-6
> > Yogi>
> >
> > JFS is a standard part of the kernel. The "utils" package contains all
> > you need for for checking it, making it and alike. Here is contents of the
> > standard distribution on RH-9:
> >
> > Yogi> rpm -ql jfsutils-1.0.17-6
> > /sbin/defragfs
> > /sbin/extendfs
> > /sbin/fsck.jfs
> > /sbin/logdump
> > /sbin/logredo
> > /sbin/mkfs.jfs
> > /sbin/xchkdmp
> > /sbin/xchklog
> > /sbin/xpeek
> > /usr/share/doc/jfsutils-1.0.17
> > /usr/share/doc/jfsutils-1.0.17/AUTHORS
> > /usr/share/doc/jfsutils-1.0.17/COPYING
> > /usr/share/doc/jfsutils-1.0.17/ChangeLog
> > /usr/share/doc/jfsutils-1.0.17/INSTALL
> > /usr/share/doc/jfsutils-1.0.17/NEWS
> > /usr/share/doc/jfsutils-1.0.17/README
> > /usr/share/man/man8/fsck.jfs.8.gz
> > /usr/share/man/man8/logdump.8.gz
> > /usr/share/man/man8/logredo.8.gz
> > /usr/share/man/man8/mkfs.jfs.8.gz
> > /usr/share/man/man8/xchkdmp.8.gz
> > /usr/share/man/man8/xchklog.8.gz
> > /usr/share/man/man8/xpeek.8.gz
> > Yogi>
> >
> > Can you please check that you have it? I'm very eager to learn, because
> that's
> > precisely the problem I reported to oracle with 10g. The result is bug#
> 3446411
> > (public) and I'm in the process of disembowelling my existing RH-9 box and
> > turning it into ES 3.0, because oracle told me that the ES 3.0 kernel may
> contain
> > the necessary ingredients to make it work.
> >
> >
> > On 02/25/2004 01:54:50 PM, "Nelson, Allan" wrote:
> > > Really, do you know where I can get JFS for RH AS 3.0? I can work from
> > > tarballs as well.
> > >
> > > Thanks
> > >
> > > -----Original Message-----
> > > From: oracle-l-bounce@xxxxxxxxxxxxx
> > > [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Mladen Gogala
> > > Sent: Wednesday, February 25, 2004 12:05 PM
> > > To: oracle-l@xxxxxxxxxxxxx
> > > Subject: Re: Moving db to linux
> > >
> > >
> > > My advice is to use JFS for database files because on 9.2.0.4, you can
> > > use direct I/O, which is supported by JFS. As far as the big files are
> > > concerned, JFS supports them without any problem.
> > >
> > > On 02/25/2004 12:22:58 PM, "Nelson, Allan" wrote:
> > > > Im, going to be moving a 220 GB 8.1.7.4 database from HP-UX to Red Hat
> > > > AS 3.0 running 9.2.0.4.0. I'm told that we have to use export/import
> > > to
> > > > get that job done. I plan to work through pipes and use split to keep
> > > > the file sizes to 2 GB or less to aviod large file issues between the
> > > > platforms. Does anyone know of other issues that may trip me up?
> > > >
> > > > Thanks In Advance
> > > >
> > > > > Allan L. Nelson
> > > > > Oracle DBA
> > > > > M-I L.L.C.
> > > > > (832) 295-2238 office
> > > > > (832) 351-4180 fax
> > > > > anelson@xxxxxxxx <mailto:anelson@xxxxxxxx>
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > ________________________________________________________________________
> > > ______
> > > > This email is intended solely for the person or entity to which it is
> > > addressed and may contain confidential and/or privileged information.
> > > Copying, forwarding or distributing this message by persons or entities
> > > other than the addressee is prohibited. If
> > > >
> > > >
> > > ----------------------------------------------------------------
> > > Please see the official ORACLE-L FAQ: http://www.orafaq.com
> > > ----------------------------------------------------------------
> > > To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
> > > put 'unsubscribe' in the subject line.
> > > --
> > > Archives are at //www.freelists.org/archives/oracle-l/
> > > FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
> > > -----------------------------------------------------------------
> > >
> > >
> > >
> ____________________________________________________________________________
> __
> > > This email is intended solely for the person or entity to which it is
> addressed and may contain confidential and/or privileged information.
> Copying, forwarding or distributing this message by persons or entities
> other than the addressee is prohibited. If you have received this email in
> error, please contact the sender immediately and delete the material from
> any computer. This email may have been monitored for policy compliance.
> [021216]
> > >
> > > ----------------------------------------------------------------
> > > Please see the official ORACLE-L FAQ: http://www.orafaq.com
> > > ----------------------------------------------------------------
> > > To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
> > > put 'unsubscribe' in the subject line.
> > > --
> > > Archives are at //www.freelists.org/archives/oracle-l/
> > > FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
> > > -----------------------------------------------------------------
> > >
> > ----------------------------------------------------------------
> > Please see the official ORACLE-L FAQ: http://www.orafaq.com
> > ----------------------------------------------------------------
> > To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
> > put 'unsubscribe' in the subject line.
> > --
> > Archives are at //www.freelists.org/archives/oracle-l/
> > FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
> > -----------------------------------------------------------------
> >
> >
>
> ----------------------------------------------------------------
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> ----------------------------------------------------------------
> To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
> put 'unsubscribe' in the subject line.
> --
> Archives are at //www.freelists.org/archives/oracle-l/
> FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
> -----------------------------------------------------------------
>
--
Mladen Gogala
Oracle DBA
----------------------------------------------------------------
Please see the official ORACLE-L FAQ: http://www.orafaq.com
----------------------------------------------------------------
To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
put 'unsubscribe' in the subject line.
--
Archives are at //www.freelists.org/archives/oracle-l/
FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
-----------------------------------------------------------------
Other related posts:
