From: Greg Freemyer Subject: Re: [PATCH 1/2] fs: Do not dispatch FITRIM through separate super_operation Date: Thu, 25 Nov 2010 11:24:22 -0500 Message-ID: References: <20101118134804.GN5618@dhcp231-156.rdu.redhat.com> <20101118141957.GK6178@parisc-linux.org> <20101118142918.GA18510@infradead.org> <1290100750.3041.72.camel@mulgrave.site> <1290168976.2570.45.camel@dolmen> <4CE68155.50705@teksavvy.com> <20101119140203.GC10039@thunk.org> <4CE69940.6040908@teksavvy.com> <20101119163013.GJ10039@thunk.org> <4CEDCE60.9050109@teksavvy.com> <4CEE7884.5010007@teksavvy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "Ted Ts'o" , Lukas Czerner , Steven Whitehouse , James Bottomley , Christoph Hellwig , Matthew Wilcox , Josef Bacik , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, sandeen@redhat.com To: Mark Lord Return-path: Received: from mail-iw0-f174.google.com ([209.85.214.174]:51861 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752546Ab0KYQYn convert rfc822-to-8bit (ORCPT ); Thu, 25 Nov 2010 11:24:43 -0500 In-Reply-To: <4CEE7884.5010007@teksavvy.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Thu, Nov 25, 2010 at 9:53 AM, Mark Lord wrote: > On 10-11-24 11:41 PM, Greg Freemyer wrote: >> >> If you see a significant speed difference between mke2fs and running >> wiper.sh on that same filesystem immediately after formatting, then >> their is likely a bug worth chasing. > > > You're right. =A0They're both equally slow on a blank Sandforce drive= , > taking about 83-90 seconds to TRIM 100GB. > > The difference being that mke2fs just sits there with zero indication > or information as to what the huge delay is. > > It's a pity the TRIM commands are so sluggish on the Sandforce. > It's a generation newer than the original Vertex, and TRIM is way fas= ter > on the older Vertex. =A0Not that either of them do it quickly enough = that > I'd ever want the kernel doing it automatically "on my behalf". > > The strange thing, is that when we TRIM the entire raw device, > using ATA SECURITY ERASE, it takes less than 2 seconds. > > Cheers Mark, I'm away from my systems today, but is there an easy way to tweak wiper.sh or hdparm to cause only a single range per trim command. I'm curious if for the Sandforce that would still be in the 90 second range, or closer to 64x that. Or if there is a readily available userspace tool to invoke FITRIM and you have a 2.6.37-rc? kernel, you could just time that on a newly formatted drive. Greg -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html