From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Pratt Subject: Re: Updated performance results Date: Fri, 11 Sep 2009 16:35:50 -0500 Message-ID: <4AAAC2B6.8040105@austin.ibm.com> References: <4A68DE81.3020505@dangyankee.net> <20090724132407.GC16192@think> <20090724140002.GD16192@think> <4A6F5BB6.4020204@austin.ibm.com> <20090728202355.GC13940@think> <4A6F6951.9020304@austin.ibm.com> <20090805203526.GE12524@think> <4A7C32A4.9070106@austin.ibm.com> <20090807231240.GD3710@think> <4A9C0D19.5010108@austin.ibm.com> <20090911192955.GB2894@think> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed To: Chris Mason , linux-btrfs Return-path: In-Reply-To: <20090911192955.GB2894@think> List-ID: Chris Mason wrote: > On Mon, Aug 31, 2009 at 12:49:13PM -0500, Steven Pratt wrote: > >> Better late than never. Finally got this finished up. Mixed bag on >> this one. BTRFS lags significantly on single threaded. Seems >> unable to keep IO outstanding to the device. Less that 60% busy on >> the DM device, compared to 97%+ for all other filesystems. >> nodatacow helps out, increasing utilization to about 70%, but still >> trails by a large margin. >> > > Hi Steve, > > Jens Axboe did some profiling on his big test rig and I think we found > the biggest CPU problems. The end result is now setting in the master > branch of the btrfs-unstable repo. > > On his boxes, btrfs went from around 400MB/s streaming writes to 1GB/s > limit, and we're now tied with XFS while using less CPU time. > > Hopefully you will see similar results ;) > Hmmm, well no I didn't. Throughputs at 1 and 128 threads are pretty much unchanged, although I do see a good CPU savings on the 128 thread case (with cow). For 16 threads we actually regressed with cow enabled. Results are here: http://btrfs.boxacle.net/repository/raid/large_create_test/write-test/1M_odirect_create.html I'll try to look more into this next week. Steve > -chris > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >