Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751825Ab0G1MgM (ORCPT ); Wed, 28 Jul 2010 08:36:12 -0400 Received: from csamuel.org ([74.50.50.137]:40728 "EHLO csamuel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750749Ab0G1MgI (ORCPT ); Wed, 28 Jul 2010 08:36:08 -0400 X-Greylist: delayed 447 seconds by postgrey-1.27 at vger.kernel.org; Wed, 28 Jul 2010 08:36:08 EDT From: Chris Samuel To: linux-btrfs@vger.kernel.org Subject: Re: [RFC PATCH 0/5] Btrfs: Add hot data tracking functionality Date: Wed, 28 Jul 2010 22:28:19 +1000 User-Agent: KMail/1.13.5 (Linux/2.6.32-24-generic; KDE/4.4.92; x86_64; ; ) Cc: Ben Chociej , diegocg@gmail.com, chris.mason@oracle.com, linux-fsdevel@vger.kernel.org, cmm@us.ibm.com, bcchocie@us.ibm.com, mrlupfer@us.ibm.com, crscott@us.ibm.com, linux-kernel@vger.kernel.org References: <1280268023-18408-1-git-send-email-bchociej@gmail.com> <201007280110.46059.diegocg@gmail.com> In-Reply-To: X-Face: Wcb;^Ll1x`\6);#5&v=2":47)c~M=K)9_=0mp[Ob~p==:85h/k)fj6nBf@^SdaXtmdYGRq [>N&^2m#i\v9ZHe:G-e=OR}-sEf`CdEL2/\).SeCBSC"Cn[(:./c*I|/3KCDO$<{n8m;X_ g\Y9LQ=v/b5`)L,WOQdI*?SqUCgiw/9`KxgdU5;z8L.3)F!1M3=w:i9MsWp&v;%usOXL;w 6kF?wAZjss.+y(78'qBu";bx]>"2dZd/S$^K)nU^N0HM\^^;s#q MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart18833409.WfW9mxhoo8"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <201007282228.23360.chris@csamuel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1916 Lines: 52 --nextPart18833409.WfW9mxhoo8 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable On Wed, 28 Jul 2010 09:18:23 am Ben Chociej wrote: > Yes, that's correct. It's likely not going to be a cache in the > traditional sense, since the entire capacity of both HDD and SSD would > be available. To me that sounds like an HSM type arrangement, with most frequently used d= ata=20 on the highest performing media and less frequently touched data getting=20 shunted down the chain to SAS, SATA and then tape and/or MAID type devices. Certainly interesting from my HPC point of view in that I can see it being= =20 useful to parallel filesystems like Ceph if this "just happens". I guess real HSM devotees would want policies for migration downstream.. ;-) cheers, Chris =2D-=20 Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC This email may come with a PGP signature as a file. Do not panic. =46or more info see: http://en.wikipedia.org/wiki/OpenPGP --nextPart18833409.WfW9mxhoo8 Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQEVAwUATFAiZI1yjaOTJg85AQKgIAgAmSg0l/BcxEJEUTLWmZbKecFUdmbanuFM ugN4G6xY/VItX5HIJmNfLtorciSBMCmHTtFelKs/FPTRIozIv3Pe7/8AZl0rCi+0 RiM+S2D15oIFyLYOKlxzh0TK4NjS+kW/Xa1xLlNdQtW77jtLZqJaSldK1n15X0Ls YwTdPRp63R3TfWqLkuPpN+M0aJmo5YfkKDyUDukSs/dEinVRQEKQZ2+oyie92Gd+ ZbIeXKJX2q1SZ6oM+4+oiL5R6sXESdEJ5IjqhkXE0FAOcPqyigPrum/pPUtymZa6 3iBbS38lwiYNDSCR6PbccRUsvstG6tFGtne+JP+dcqP4JWpJKiQriQ== =HETq -----END PGP SIGNATURE----- --nextPart18833409.WfW9mxhoo8-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/