From owner-freebsd-stable@freebsd.org Wed Nov 18 10:07:14 2015 Return-Path: Delivered-To: freebsd-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 0C161A320C5; Wed, 18 Nov 2015 10:07:14 +0000 (UTC) (envelope-from slw@zxy.spb.ru) Received: from zxy.spb.ru (zxy.spb.ru [195.70.199.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id B9EDA113C; Wed, 18 Nov 2015 10:07:13 +0000 (UTC) (envelope-from slw@zxy.spb.ru) Received: from slw by zxy.spb.ru with local (Exim 4.86 (FreeBSD)) (envelope-from ) id 1Zyzdt-0001PA-LE; Wed, 18 Nov 2015 13:07:09 +0300 Date: Wed, 18 Nov 2015 13:07:09 +0300 From: Slawa Olhovchenkov To: Garrett Wollman Cc: freebsd-fs@freebsd.org, freebsd-stable@freebsd.org Subject: Re: Some filesystem performance numbers Message-ID: <20151118100709.GN48728@zxy.spb.ru> References: <21685.40094.453028.585630@hergotha.csail.mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <21685.40094.453028.585630@hergotha.csail.mit.edu> User-Agent: Mutt/1.5.24 (2015-08-30) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: slw@zxy.spb.ru X-SA-Exim-Scanned: No (on zxy.spb.ru); SAEximRunCond expanded to false X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 Nov 2015 10:07:14 -0000 On Tue, Jan 13, 2015 at 05:30:54PM -0500, Garrett Wollman wrote: > I recently bought a copy of the SPECsfs2014 benchmark, and I've been > using it to test out our NFS server platform. One scenario of > interest to me is identifying where the limits are in terms of the > local CAM/storage/filesystem implementation versus bottlenecks unique > to the NFS server, and to that end I've been running the benchmark > suite directly on the server's local disk. (This is of course also > the way you'd benchmark for shared-nothing container-based > virtualization.) > > I have found a few interesting results on my test platform: > > 1) I can quantify the cost of using SHA256 vs. fletcher4 as the ZFS > checksum algorithm. On the VDA workload (essentially a simulated > video streaming/recording application), my server can do about half as > many "streams" with SHA256 as it can with fletcher4. For VDA recordsize=1M (or more) can give performance impcat in case saturated HDD by IOPS. > 2) Both L2ARC and separate ZIL have small but measurable performance > impacts. I haven't examined the differences closely. This is depend of fractions hot/warm/cold content. > 3) LZ4 compression also makes a small performance impact, but as > advertised, less than LZJB for mostly-incompressible data. > > I hope to be able to present the actual benchmark results at some > point, as well as some results for the other three workloads. > > -GAWollman > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org"