From owner-freebsd-performance@FreeBSD.ORG Thu Jan 31 16:55:59 2008 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6F58A16A418 for ; Thu, 31 Jan 2008 16:55:48 +0000 (UTC) (envelope-from ndenev@gmail.com) Received: from rv-out-0910.google.com (rv-out-0910.google.com [209.85.198.184]) by mx1.freebsd.org (Postfix) with ESMTP id C5B8113C442 for ; Thu, 31 Jan 2008 16:55:47 +0000 (UTC) (envelope-from ndenev@gmail.com) Received: by rv-out-0910.google.com with SMTP id g13so652205rvb.43 for ; Thu, 31 Jan 2008 08:55:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:sender:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; bh=cjxN3attjNZa1Rc5Xc4OUIXA0MUYGDu60sIQgugTZIg=; b=iJ7RV/UG2B4zaPBxhDByYm8NCrcHoqqByNwi1mpYxSSJtQY9O3SuNUQoFM00780PiEWsMwcw0ywYep91/ZB7aTFWKH/Z4dyqJT1QnRQ4PDHh7f7MC8Wy9KkHBHW3VoE1DU4cmLws1cb+T1N7V1Vjzui0kOS5fjf3TDmm0TqYPkA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:sender:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=spl/pyJtCFiVpGA6doyRhD/xS43lt5aepE3VXs+cmfjNDAkwLUcKjnuD14ctdWuNFFRTDRmoV8PYzsK+4IuHbOXyQmk16ZuqffoYaVAgJsd9cpi44blrowx2m8p0TvftTuTF7dNygg5rASwpIBSA3ni6f1SupsPhBoUAHGym1pw= Received: by 10.141.170.10 with SMTP id x10mr1584137rvo.139.1201796795403; Thu, 31 Jan 2008 08:26:35 -0800 (PST) Received: by 10.141.170.18 with HTTP; Thu, 31 Jan 2008 08:26:35 -0800 (PST) Message-ID: <2e77fc10801310826v2fabb5g594840241784fc7@mail.gmail.com> Date: Thu, 31 Jan 2008 18:26:35 +0200 From: "Niki Denev" Sender: ndenev@gmail.com To: freebsd-performance@freebsd.org In-Reply-To: <9bbcef730801301157n25684018y3d43bfdd0301a8dd@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <479E3C5E.1070405@FreeBSD.org> <47A043FD.9090607@FreeBSD.org> <47A0CD11.802@FreeBSD.org> <9bbcef730801301157n25684018y3d43bfdd0301a8dd@mail.gmail.com> X-Google-Sender-Auth: b9288bb34249e843 X-Mailman-Approved-At: Thu, 31 Jan 2008 17:13:47 +0000 Subject: Re: postgresql-performance using sysbench X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 31 Jan 2008 16:55:59 -0000 On Jan 30, 2008 9:57 PM, Ivan Voras wrote: > On 30/01/2008, Kris Kennaway wrote: > > > Rewrite of the lockmgr primitive, for starters. Then we'll see what > > remains. > > Ok, I know about the lockmgr efforts, and they will surely help some > loads. I'll try to compile the results I've been talking about in a > few days and post them. > Just a thought on the effect that HZ has on filesystem (and overall) performance : Linux has sort of backtracked from defaulting to HZ=1000 and enable it only on kernels compiled for "Desktop" work, and setting HZ=250 for the "Server" profile. A very quick /usr/ports/benchmarks/postmark benchmark on my machine (FreeBSD 7.0 PREREL with ULE on dualcore C2D) shows this : HZ=1000 Time: 239 seconds total 122 seconds of transactions (4 per second) Files: 749 created (3 per second) Creation alone: 500 files (4 per second) Mixed with transactions: 249 files (2 per second) 267 read (2 per second) 233 appended (1 per second) 749 deleted (3 per second) Deletion alone: 498 files (498 per second) Mixed with transactions: 251 files (2 per second) Data: 573.06 megabytes read (2.40 megabytes per second) 1699.49 megabytes written (7.11 megabytes per second) HZ=250 Time: 178 seconds total 79 seconds of transactions (6 per second) Files: 749 created (4 per second) Creation alone: 500 files (5 per second) Mixed with transactions: 249 files (3 per second) 267 read (3 per second) 233 appended (2 per second) 749 deleted (4 per second) Deletion alone: 498 files (498 per second) Mixed with transactions: 251 files (3 per second) Data: 573.06 megabytes read (3.22 megabytes per second) 1699.49 megabytes written (9.55 megabytes per second) A measurable increase in performance when using HZ=250, at least in this simple benchmark. The question is do we need such sort of profiles as in Linux, i.e. HZ=250 for servers and HZ=1000 for desktops. Of course anyone can set HZ to whatever value he likes, but maybe it should be better if it is documented with some advisory settings for different workloads (server/desktop). What do you think? P.S.: Maybe it would be interesting to see how FreeBSD compares to Linux with equal HZ settings on the benchmark in the first post?