From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753151Ab0BKMWv (ORCPT ); Thu, 11 Feb 2010 07:22:51 -0500 Received: from bombadil.infradead.org ([18.85.46.34]:37201 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751998Ab0BKMWt (ORCPT ); Thu, 11 Feb 2010 07:22:49 -0500 Date: Thu, 11 Feb 2010 07:22:49 -0500 From: Christoph Hellwig To: Dmitry Monakhov Cc: linux-kernel@vger.kernel.org, jens.axboe@oracle.com Subject: Re: [PATCH 2/4] block: support compat discard mode by default. Message-ID: <20100211122249.GB12417@infradead.org> References: <1265885625-21608-1-git-send-email-dmonakhov@openvz.org> <1265885870-21858-1-git-send-email-dmonakhov@openvz.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1265885870-21858-1-git-send-email-dmonakhov@openvz.org> User-Agent: Mutt/1.5.19 (2009-01-05) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 11, 2010 at 01:57:50PM +0300, Dmitry Monakhov wrote: > Currently there are many filesystems which has implemented > discard support, but ssd discs not widely used yet. > Let's allow user to use compat discard mode by default. > After this feature is enabled by default for all devices which has > no native discard support it will be possible to use this feature > simply by passing appropriate mount option to fs (-odiscard in ext4) So why do you even bother adding the DISCARD_FL_COMPAT option? This is a debug option that should probably be controlled at the block level, not anywhere near the filesystem.