Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758171Ab0FJIUF (ORCPT ); Thu, 10 Jun 2010 04:20:05 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:49153 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752064Ab0FJIUB (ORCPT ); Thu, 10 Jun 2010 04:20:01 -0400 Date: Thu, 10 Jun 2010 04:19:50 -0400 From: Christoph Hellwig To: Adrian Hunter Cc: Jens Axboe , Andrew Morton , "linux-mmc@vger.kernel.org" , LKML , Christoph Hellwig Subject: Re: [PATCH 1/4] block: Allow drivers to implement BLKDISCARD and add BLKSECDISCARD Message-ID: <20100610081950.GA15888@infradead.org> References: <4C081AEC.7010302@nokia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4C081AEC.7010302@nokia.com> User-Agent: Mutt/1.5.20 (2009-08-17) 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 Content-Length: 853 Lines: 17 On Fri, Jun 04, 2010 at 12:13:16AM +0300, Adrian Hunter wrote: > SD/MMC cards provide an erase operation that is too inefficient to > allow file systems to use it, however it is still useful for > userspace tools because it is still 10 - 100 times faster than > writing zeroes. Allow the MMC block driver to provide its own > BLKDISCARD implementation for this purpose. That's no good reason. Almost all current SSD TRIM implementations have the same issue, that's why filesustems require the -o discard option to enabled it. In addition I've not actually seen any numbers from you on a current kernel. -- 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/