From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o9T7um44117894 for ; Fri, 29 Oct 2010 02:56:49 -0500 Received: from mailsrv14.zmi.at (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 1BBE219AE30E for ; Fri, 29 Oct 2010 00:58:06 -0700 (PDT) Received: from mailsrv14.zmi.at (mailsrv1.zmi.at [212.69.164.54]) by cuda.sgi.com with ESMTP id gO9y4bVlTBB0KlkH for ; Fri, 29 Oct 2010 00:58:06 -0700 (PDT) From: Michael Monnerie Subject: Re: XFS journaling position Date: Fri, 29 Oct 2010 09:58:02 +0200 References: <31c7e56286d37870011c17ee8e002760.squirrel@webmail.ics.forth.gr> <201010281144.39307@zmi.at> <4CCA0834.8040703@hardwarefreak.com> In-Reply-To: <4CCA0834.8040703@hardwarefreak.com> MIME-Version: 1.0 Message-Id: <201010290958.03513@zmi.at> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============6927327742429245564==" Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com Cc: Stan Hoeppner --===============6927327742429245564== Content-Type: multipart/signed; boundary="nextPart3334121.c5ahA3UjF7"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit --nextPart3334121.c5ahA3UjF7 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable On Freitag, 29. Oktober 2010 Stan Hoeppner wrote: > So as we move to a totally virtualized guest OS, we then lose the > stripe width and stripe size information. How much performance does > this really cost us WRT XFS filesystem layout? =20 This is still a very straightforward config. When you use a NetApp=20 storage with virtualization, you normally use thin provisioning. So you=20 put one VM with it's root FS on that system, and assign a data disk of=20 1.4TB. You then "flexclone" that VM 9 times, so you have 10 VMs running=20 but they only use the diskspace of one. Then you upgrade or modify one=20 VM, and only the blocks that are modified get copied on the disks.=20 You fill 5 VMs in parallel with data, and it gets stored totally=20 "fragmented" on the storage. Now do a snapshot of a VM, so it's old=20 contents are frozen and every write gets written to a new place. There are companies who do a snapshot of every VM every hour, so their=20 users can by themself recover files that they deleted/modifed wrongly. And now take into account that NetApp uses WAFL - write anywhere file=20 layout. It means that even if you have a VM straight on disk, as soon as=20 you modify a block it can be written in a totally different place on the=20 storage. I'd say this is such a "total mess" where you know exactly *nothing*=20 about the layout of anything. You cannot even optimize for stripe size. > How many folks are running their > critical core business databases in virtual machine guests? How > about core email systems? Other performance/business critical > applications? I don't know which country you are from, I'm from Austria/Europe (not=20 the kangaroo country :-). On every single tech talk and presentation I=20 visited this year, every single speaker talked about virtualization.=20 Depending on who spoke, either 2009 or 2010 were the years where more=20 virtual servers were deployed than physical ones, with a sharp increase=20 each year. We didn't sell a single server running bare-metal OS, all had=20 VMware or XenServer. And for business critical: SAP uses virtualization everywhere in-house,=20 =D6BB (Austrian Railways) use Xen for virtualized central accounting=20 program since 2001 exclusively. These are just the 2 companies who were=20 speaking on last weeks presentation, there are far more. =2D-=20 mit freundlichen Gr=FCssen, Michael Monnerie, Ing. BSc it-management Internet Services http://proteger.at [gesprochen: Prot-e-schee] Tel: 0660 / 415 65 31 ****** Radiointerview zum Thema Spam ****** http://www.it-podcast.at/archiv.html#podcast-100716 // Wir haben im Moment zwei H=E4user zu verkaufen: // http://zmi.at/langegg/ // http://zmi.at/haus2009/ --nextPart3334121.c5ahA3UjF7 Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (GNU/Linux) iEYEABECAAYFAkzKfosACgkQzhSR9xwSCbSx+ACfRT+2oMfx2ynOjTtDZbTaRDBZ c4kAn0UX30gm1KRnSfB/I9v6diczcKrR =8xo+ -----END PGP SIGNATURE----- --nextPart3334121.c5ahA3UjF7-- --===============6927327742429245564== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs --===============6927327742429245564==--