From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Layton Subject: Re: TRIM support in drivers and dm/md? Date: Thu, 04 Nov 2010 13:56:49 -0400 Message-ID: <4CD2F3E1.8040700@att.net> References: <4CD2B2EF.4050005@att.net> <20101104134014.GB21931@parisc-linux.org> <4CD2C755.3000908@att.net> <4CD2E32D.9030303@garzik.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Matthew Wilcox , linux-fsdevel@vger.kernel.org To: Jeff Garzik Return-path: Received: from nm21-vm0.bullet.mail.ne1.yahoo.com ([98.138.90.94]:37235 "HELO nm21-vm0.bullet.mail.ne1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750828Ab0KDR5H (ORCPT ); Thu, 4 Nov 2010 13:57:07 -0400 In-Reply-To: <4CD2E32D.9030303@garzik.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: >>>> Do many of the SATA controllers support TRIM? (i.e. pass >>>> the TRIM command to the SSD). Does anyone know >>>> anything about dm/md supporting TRIM? (I'm thinking LVM >>>> and software RAID tools). > >>> As far as I know, there's nothing to be done in any SATA controller >>> driver to support TRIM. It's just up to the drive whether it >>> understands >>> the command. > >> That's the rub. I've heard that many drivers don't understand >> the command. So I'm curious what drivers do and any experience >> anyone might have. > > Note the distinction between "drive" and "driver"... I agree with > what Matthew says. > Oops - sorry I missed "drive" vs. "driver". I've heard from other places that drivers need to pass along the TRIM command to the drives but that many drivers don't do this. I assume that the best way to determine if this is accurate is to test the controller drivers or ping the maintainers. Thanks!