Antwort: Re: [Ocfs2-users] OCFS2 vs Oracle ASM CFS
From: Martin Klier <Martin.Klier_at_klug-is.de>
Date: Wed, 16 Sep 2009 09:05:55 +0200
Date: Wed, 16 Sep 2009 09:05:55 +0200
a friend did a basic test on OCFS2 lately. No breaking news, just another dd test.
-- Mit freundlichem Gruß Martin Klier Senior Oracle Database Administrator ------------------------------------------------------------------------------ Klug GmbH integrierte Systeme Lindenweg 13, D-92552 Teunz Tel.: +49 9671/9216-245 Fax.: +49 9671/9216-112 mailto: martin.klier_at_klug-is.de www.klug-is.de ------------------------------------------------------------------------------ Geschäftsführer: Johann Klug, Roman Sorgenfrei Sitz der Gesellschaft: Teunz, USt-ID-Nr. DE175481608, HRB Nr. 2037, Amtsgericht Amberg oracle-l-bounce_at_freelists.org schrieb am 03.09.2009 21:48:05:Received on Wed Sep 16 2009 - 02:05:55 CDT
> Jeremy Schneider <jeremy.schneider_at_ardentperf.com>
> Sunil Mushran <sunil.mushran_at_oracle.com>
> "ocfs2-users_at_oss.oracle.com" <ocfs2-users_at_oss.oracle.com>, "oracle-
> l_at_freelists.org" <oracle-l_at_freelists.org>
> 03.09.2009 21:51
> Re: [Ocfs2-users] OCFS2 vs Oracle ASM CFS
> Gesendet von:
> Thanks Sunil (and Joel) -
> Sorry, I typed that email a little too fast - I meant to say ZFS (from
> Sun), not XFS. I'll have to read up on the REFLINKS -- apologies that I
> hadn't caught that before; it sounds quite good!
> While I disagree quite strongly with the sentiment, it's amazing how
> many people I still come across who view OCFS2 as a very "immature"
> filesystem. Very recently, some folks I know who are running hundreds
> of RAC on Solaris deployments (with shared oracle homes on a cluster
> filesystem) came up with their Linux RAC plans. They could potentiall
> roll out a few hundred clusters of this configuration too... and they
> chose to complicate their deployment by switching OCFS2 mounts to
> non-cluster local filesystem whenever possible -- in large part because
> they didn't view OCFS2 as "reliable" enough. (I really tried as hard as
> I could to convince them otherwise... IMHO it was a poor decision.)
> With the announcement of ACFS, I imagine that the FUD will persist... so
> it's good to hear that you guys are regularly stress testing your OCFS2
> releases with database workloads. Sometime I'd be interested to hear
> more about what kind of stress testing you do, especially for
> non-datafiles (oracle homes and other general purpose uses).
> Also, on a side note, I was recently at a site where they create
> tempfiles as sparse on solaris; not sure if that might be an additional
> [1.4?] feature of OCFS2 that would be useful for databases.
> And thanks again for the response... I guess the hazard of a public
> list is that you get the occasional dumb email, and after re-reading it,
> I think that my earlier email sounded a little more obnoxious than I
> meant it to... I'm glad you put up with me and gave such great
> Sunil Mushran wrote:
> > Jeremy Schneider wrote:
> >> Some quick questions for the ocfs2-users list, now that 11.2 is
> >> public. (Now that it's public knowledge that Oracle developed a whole
> >> new
> >> [propriatery] cluster filesystem from the ground up for RAC.)
> >> 1) Seems that the 11.2 docs encourage using ACFS rather than OCFS2 for
> >> oracle binaries. Would it be safe to say that OCFS2 isn't strategic
> >> all anymore for Oracle database files? I've also noticed that OCFS2
> >> the underlying filesystem in Oracle VM. Is this a shift in strategy
> >> OCFS2? As a development team, are you guys increasing your focus on
> >> Oracle VM? I wouldn't expect that Oracle would continue to invest in
> >> OCFS2 development only for the benefit of SLES...
> > OCFS2 was not developed for any one use case. It was always meant to
> > be for
> > general purpose usage. While most of our early users were using it
> > primarily
> > with the database, we have come a long way since then.
> > There is no shift in strategy. OCFS2 is still stress tested with the
> > database
> > by multiple groups. As far as development effort goes, we took care of
> > db usage
> > in our first release. In 1.0 we had support for directio, asyncio,
> > extents and
> > large files. And the performance was in line with raw. Frankly, the
> > database
> > does not expect much more than that from the file system.
> > In 1.4, we added unwritten extents that could one day be used by the
> > database.
> > But mostly the new features were targeted towards general purpose
> > The story will not change in 1.6.
> > http://oss.oracle.com/osswiki/OCFS2/Roadmap
> > Yes, OracleVM is an important user of OCFS2. So we are obviously
> > focused on it.
> > But not at the expense of other users.
> > Oracle is not focused on OCFS2 for SLES. Novell takes care of that.
> > Oracle is
> > focused on OCFS2 for EL.
> >> 2) I'm curious if anyone has tried running OCFS2 on DVM? Would there
> >> any point to using OCFS2 rather than ACFS?
> > I believe OCFS2 has been tested with ADVM. It works with one big
> > In OCFS2, we heartbeat in the fs itself. That is a problem if ADVM
> > were to
> > freeze the ios temporarily for say resilvering. We intend to fix this
> > issue by
> > dusting off the global heartbeat patches that allows users to specify
> > a different
> > heartbeat device. Hopefully in 1.6.
> >> 3) ACFS shapshots -- or are those a feature of DVM? Seems like a
> >> feature - isn't xfs the only other currently released filesystem to
> >> support this? Any plans to add snapshots to the OCFS2 roadmap?
> > No, XFS does not support snapshots. The only mainstream Linux fs to
> > support
> > snapshots is BTRFS. (unlimited writable snapshots). Still not PROD
> > though.
> > http://oss.oracle.com/projects/btrfs/
> > We have no current plans on supporting traditional volume based
> > snapshots.
> > What we are working on instead is REFLINKs, which is inode-based
> > snapshots. I talked about it in the email announcing the 1.4.2 release.
> > http://oss.oracle.com/pipermail/ocfs2-announce/2009-June/000028.html
> >> This is why I've always loved OCFS2 so much to start with -- there is
> >> "asm-users" or "asm-devel" mailing list. :)
> >> -Jeremy
> >> http://download.oracle.com/docs/cd/E11882_01/server.112/e10500/
> Jeremy Schneider
> Chicago, IL