From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [RFC 1/2] block: implement an unprep function corresponding directly to prep Date: Mon, 05 Jul 2010 18:00:28 -0400 Message-ID: <4C3255FC.9060503@garzik.org> References: <1277917264.2839.153.camel@mulgrave.site> <20100701104653O.fujita.tomonori@lab.ntt.co.jp> <20100702110343.GA27159@lst.de> <20100705160023S.fujita.tomonori@lab.ntt.co.jp> <20100705192413.GA24189@lst.de> <4C3253C0.8040900@teksavvy.com> <4C3254A3.6080709@teksavvy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-gx0-f174.google.com ([209.85.161.174]:47871 "EHLO mail-gx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754789Ab0GEWAb (ORCPT ); Mon, 5 Jul 2010 18:00:31 -0400 In-Reply-To: <4C3254A3.6080709@teksavvy.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Mark Lord Cc: Christoph Hellwig , FUJITA Tomonori , James.Bottomley@suse.de, snitzer@redhat.com, axboe@kernel.dk, linux-scsi@vger.kernel.org, dm-devel@redhat.com, linux-ide@vger.kernel.org On 07/05/2010 05:54 PM, Mark Lord wrote: >> On 05/07/10 03:24 PM, Christoph Hellwig wrote: >>> >>> What codebase were you testing on? Sorry, but curently I'm a bit lost >>> in the maze of patches. I've got both and intel and an OCZ SSD > .. > > Do you, or anyone else with one, know what the upper limit is on > TRIM operations with the Intel SSDs ? > > I need to know the maximum amount of TRIM ranges they will process > in a single command. > > Eg. Indilinx-based SSDs don't appear to have a limit -- they'll accept > a TRIM command with thousands of LBA ranges included. > > Sandforce-based SSDs appear to restrict things to max 4KB of range data. > > So.. what about Intel? Lovely :( I wonder if we could test for that limit at mke2fs time, or similar. Seeing a 4k limit on other SSDs would not surprise me. Or even a 512-b limit. Jeff