Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758306Ab0FKHwO (ORCPT ); Fri, 11 Jun 2010 03:52:14 -0400 Received: from mail-pv0-f174.google.com ([74.125.83.174]:35935 "EHLO mail-pv0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752868Ab0FKHwM convert rfc822-to-8bit (ORCPT ); Fri, 11 Jun 2010 03:52:12 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=iKe40kObMFgt/cy8bDNNwZDDnjgrAHoSIUlAou4cYnMHllb9Q89bfvXsMxJBgd2z9C URRKGPN5ThbJzJ7kJl+qiJBkDUFp6j/lC/xoUObiVYi/Ikheqd1IpSoCFxFeGFn9tQ5Y tgSCuPyL60ElTqSAS/1h589vKWMUQLiwBIS4c= MIME-Version: 1.0 In-Reply-To: <20100610081950.GA15888@infradead.org> References: <4C081AEC.7010302@nokia.com> <20100610081950.GA15888@infradead.org> Date: Fri, 11 Jun 2010 16:52:11 +0900 X-Google-Sender-Auth: buQjaha1WKFxIA1XzlMNmoPRbrU Message-ID: Subject: Re: [PATCH 1/4] block: Allow drivers to implement BLKDISCARD and add BLKSECDISCARD From: Kyungmin Park To: Christoph Hellwig Cc: Adrian Hunter , Jens Axboe , Andrew Morton , "linux-mmc@vger.kernel.org" , LKML 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: 1548 Lines: 38 On Thu, Jun 10, 2010 at 5:19 PM, Christoph Hellwig wrote: > 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. I heard if we give trim command without proper align, it writes some data to align its data. then user data can be corrupt. The main problem is we don't know exact used block at filesystem. so user can corrupt their data easily. And as you know each manufacturers use their own superpage and align. > > 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. I hope to see the performance results. In my test, no improvement. Thank you, Kyungmin Park > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at ?http://vger.kernel.org/majordomo-info.html > -- 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/