From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id C2FF329DF8 for ; Tue, 4 Jun 2013 17:09:10 -0500 (CDT) Date: Tue, 4 Jun 2013 17:09:10 -0500 From: Ben Myers Subject: Re: Debunking myths about metadata CRC overhead Message-ID: <20130604220910.GS19505@sgi.com> References: <20130603074452.GZ29466@dastard> <20130603111011.461d10b5@galadriel.home> <20130604025307.GB29466@dastard> <20130604162030.GJ20932@sgi.com> <20130604220610.GJ29466@dastard> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20130604220610.GJ29466@dastard> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com On Wed, Jun 05, 2013 at 08:06:10AM +1000, Dave Chinner wrote: > On Tue, Jun 04, 2013 at 11:20:30AM -0500, Ben Myers wrote: > > Dave, > > = > > On Tue, Jun 04, 2013 at 12:53:07PM +1000, Dave Chinner wrote: > > > On Mon, Jun 03, 2013 at 11:10:11AM +0200, Emmanuel Florac wrote: > > > > Le Mon, 3 Jun 2013 17:44:52 +1000 vous =E9criviez: > > > > = > > > > > There has been some assertions made recently that metadata CRCs h= ave > > > > > too much overhead to always be enabled. So I'll run some quick > > > > > benchmarks to demonstrate the "too much overhead" assertions are > > > > > completely unfounded. > > > > = > > > > Just a quick question: what is the minimal kernel version and xfspr= ogs > > > > version needed to run xfs with metadata CRC? I'd happily test it on > > > > real hardware, I have a couple of storage servers in test in the 40= to > > > > 108 TB range. > > > = > > > If the maintainers merge all the patches I send for the 3.10-rc > > > series, then the 3.10 release should be stable enough to use for > > > testing with data you don't care if you lose. > > > = > > > As for the userspace code - that is still just a patchset. I haven't > > > had any feedback from the maintainers about it in the past month, so > > > I've got no idea what they are doing with it. I'll post out a new > > > version in the next couple of days - it's 50-odd patches by now, so > > > it'd be nice to have it in the xfsprogs git tree so people could > > > just pull it and build it for testing purposes by the time that 3.10 > > > releases.... > > = > > When it is reviewed and adequately tested we'll pull it in. Until then > > Emmanuel will need to pull down the patchset. Right now the focus is on > > 3.10. > = > And when will that be? I've already been waiting the best part of a > month for anyone to even comment on it, and I've got 5 private pings > in the past 3 days asking about how to get the userspace code so > they can test the new kernel code.... > = > How about this: I post an up-to-date patch set, and you guys commit > it to a "crc-dev" branch in the oss xfsprogs git tree. The branch > can be thrown away when the code is reviewed, but in the mean time > we can point early adopters and testers to that branch rather than > ask them to pull down and apply a 50 patch series to a git tree? Sounds good to me. -Ben _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs