From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tracy Reed Subject: Re: [RFC PATCH 0/5] Btrfs: Add hot data tracking functionality Date: Tue, 27 Jul 2010 15:29:16 -0700 Message-ID: <20100727222916.GM18595@tracyreed.org> References: <1280268023-18408-1-git-send-email-bchociej@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="9/eUdp+dLtKXvemk" Cc: chris.mason@oracle.com, linux-btrfs@vger.kernel.org, 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 To: bchociej@gmail.com Return-path: Content-Disposition: inline In-Reply-To: <1280268023-18408-1-git-send-email-bchociej@gmail.com> Sender: linux-btrfs-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org --9/eUdp+dLtKXvemk Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jul 27, 2010 at 05:00:18PM -0500, bchociej@gmail.com spake thusly: > The long-term goal of these patches, as discussed in the Motivation > section at the end of this message, is to enable Btrfs to perform > automagic relocation of hot data to fast media like SSD. This goal has > been motivated by the Project Ideas page on the Btrfs wiki. With disks being so highly virtualized away these days is there any way for btrfs to know which are the fast outer-tracks vs the slower inner-tracks of a physical disk? If so not only could this benefit SSD owners but it could also benefit the many more spinning platters out there. If not (which wouldn't be surprising) then disregard. Even just having that sort of functionality for SSD would be excellent. If I understand correctly not only would this work for SSD but if I have a SAN full of many large 7200rpm disks and a few 15k SAS disks I could effectively utilize that disk by allowing btrfs to place hot data on the 15k SAS. I understand Compellent does this as well. --=20 Tracy Reed http://tracyreed.org --9/eUdp+dLtKXvemk Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) iD8DBQFMT128BhSTPg0d/nQRAhBOAKCvjeQkmnXPZfOKLMH77Uqf/wq/eQCg3Jlj bLgbNEtYOD8rwMexPC+8lOU= =jetJ -----END PGP SIGNATURE----- --9/eUdp+dLtKXvemk--