From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phillip Susi Subject: SSHD ( Hybrid drive ) cache pinning Date: Sun, 16 Nov 2014 21:02:23 -0500 Message-ID: <5469572F.50809@ubuntu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit To: linux-fsdevel Return-path: Received: from cdptpa-outbound-snat.email.rr.com ([107.14.166.229]:3937 "EHLO cdptpa-oedge-vip.email.rr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751026AbaKQCCZ (ORCPT ); Sun, 16 Nov 2014 21:02:25 -0500 Sender: linux-fsdevel-owner@vger.kernel.org List-ID: -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Hybrid hard drives are coming to market ( I will soon have one for testing ) that use flash to cache the rotating media. While the drive firmware will attempt to figure out what blocks you frequently access randomly ( not streaming IO ), and try to cache them in the flash, ATA8 does add commands to allow the OS to explicitly control what blocks are cached, and it should be in a better position to know what should be there than the heuristics in the drive firmware. Has there been any work done yet ( or even just design ) on implementing this in linux? -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBCgAGBQJUaVcvAAoJENRVrw2cjl5RN2cH/iU7qywRvAqOq5jSw2nbHTV/ eD6C6QTIcL60yGld0TFXb/NC54kJkhBsciRZkc4IVZ0OakGubrVL9IrKbcluAoAW 5bleJrqZ/EKTaGRC52tH1XEO3XWsjMGwoK2KqhcAyCFUnuz/3nM138oJr5rbGetq Y+DqE8uNrCrxiVEDOxaLSNuBrGT7h/EL1jaLLBb2OUrgBJrgoY3WRjiQqBsBLCMq uA02FP7Ol/agrUdHQeMuX/9B2ayyHPdRmKrhf1/DNJ9RHdZQBwuPbbDeIlH/7eqe lrSKSq4Ek/VJ6Uyb2ja0A2E/lcWymn/XEhFmOYsBt2Lpw2Bnk/AHtnwTKvt7HY4= =NUAs -----END PGP SIGNATURE-----