Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934489Ab0HMONl (ORCPT ); Fri, 13 Aug 2010 10:13:41 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:46051 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934288Ab0HMONi convert rfc822-to-8bit (ORCPT ); Fri, 13 Aug 2010 10:13:38 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-type:content-transfer-encoding; b=r+8FXg4U26tcImXCt2A1rNpZemjiJEKhLnTWWpF/ToRfWivWT0SHjiY2RupVycnp7L XZmSbSlf9xO2ESCSO7s22LyHpsA4i/knJYC1lrm7NbNZCNsTsK6ZOg1OqztZPmvl84Au WUG54eTKmzopu+gz8L0FzFy7gvkymJJvJQw1s= MIME-Version: 1.0 In-Reply-To: <20100813140810.GB24029@mother.pipebreaker.pl> References: <1281652177-23562-1-git-send-email-bchociej@gmail.com> <1281652177-23562-3-git-send-email-bchociej@gmail.com> <20100813131422.GA615@centrinvest.ru> <20100813140810.GB24029@mother.pipebreaker.pl> From: Ben Chociej Date: Fri, 13 Aug 2010 09:12:41 -0500 Message-ID: Subject: Re: [PATCH 2/2] Btrfs-progs: Add hot data support in mkfs To: linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, bchociej@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, mlupfer@gmail.com, conscott@vt.edu Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1591 Lines: 35 On Fri, Aug 13, 2010 at 9:08 AM, Tomasz Torcz wrote: > On Fri, Aug 13, 2010 at 05:14:22PM +0400, Andrey Panin wrote: >> On 224, 08 12, 2010 at 05:29:37PM -0500, bchociej@gmail.com wrote: >> > From: Ben Chociej >> > >> > Modified mkfs.btrfs to add hot data relocation option (-h) which >> > preallocates BTRFS_BLOCK_GROUP_DATA_SSD and >> > BTRFS_BLOCK_GROUP_METADATA_SSD at mkfs time for future use by hot data >> > relocation code. ?Also added a userspace function to detect whether a >> > block device is an SSD by reading the sysfs block queue rotational flag. >> >> IMHO this policy is too inflexible. What if I have large array of slow SATA >> disks and some fast SAS ones ? > > ?I'm hoping that this is just first cut, and future versions will have options. > For now, it is totally unusable without a way of using mirrored SSD for > hot data. > ?Ideally, hot storage devices should be online selectable and changeable. > > -- > Tomasz Torcz ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 72->| ? 80->| > xmpp: zdzichubg@chrome.pl ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?72->| ? 80->| > > This is very much just a first cut. Our goal here was to get a lot of the legwork and experimental coding out of the way to enable to Btrfs to *fully* tackle heterogeneous storage in the future. BC -- 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/