From owner-freebsd-performance@FreeBSD.ORG Fri Feb 1 08:24:16 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 2C50516A41A for ; Fri, 1 Feb 2008 08:24:16 +0000 (UTC) (envelope-from kometen@gmail.com) Received: from an-out-0708.google.com (an-out-0708.google.com [209.85.132.251]) by mx1.freebsd.org (Postfix) with ESMTP id D8D0813C46A for ; Fri, 1 Feb 2008 08:24:15 +0000 (UTC) (envelope-from kometen@gmail.com) Received: by an-out-0708.google.com with SMTP id c14so296377anc.13 for ; Fri, 01 Feb 2008 00:24:15 -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:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=dTdsI3lfeoCKIKNNM3ghUpEK5biONX2Ipu2WRGqKf4s=; b=oZdQWFghT4OO2iVudFzC3Ftmy0RUQJebQuNeveikIEKHt796SXUNrl2Q+8GegnPHvIGfCWAQcYQkjbig/OoO6RmQOwuBIiSaBlwgPCQQhZHx2QhsSFdYx9Ivv6PdxETHU7LLL1MzL9ijGbF+/2kHTAAaOz1XUsd7yw1ZqxnChVk= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=JBSYHHqulwgqsOJHQuVCNEEV9AC9nLIld//wMnqB8EcPUMBY+t6Tf0huXq1MXjUv4Tm+nNhfr2DhSgkRp8sPztXW66nark2lOjKmqsMF6zueJicLD55cjvZYWHer6hKeeo0a6qSWkARAifsPNk700iL4IyaN8/QAnfJb5ZcLHX0= Received: by 10.100.249.9 with SMTP id w9mr6713722anh.67.1201854255208; Fri, 01 Feb 2008 00:24:15 -0800 (PST) Received: by 10.100.242.10 with HTTP; Fri, 1 Feb 2008 00:24:15 -0800 (PST) Message-ID: Date: Fri, 1 Feb 2008 09:24:15 +0100 From: "Claus Guttesen" To: "Niki Denev" In-Reply-To: <2e77fc10801310826v2fabb5g594840241784fc7@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> <2e77fc10801310826v2fabb5g594840241784fc7@mail.gmail.com> Cc: freebsd-performance@freebsd.org 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: Fri, 01 Feb 2008 08:24:16 -0000 > 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. I'm doing some db-imports on postgresql on a file which takes 3 hours and 40 min. with default HZ (1000). Then I changed HZ to 250 (in loader.conf) and rebooted. The import still took 3 h. 40 min. so altering HZ does not seem to have any influence. #>sysctl kern.clockrate kern.clockrate: { hz = 250, tick = 4000, profhz = 166, stathz = 33 } -- regards Claus When lenity and cruelty play for a kingdom, the gentlest gamester is the soonest winner. Shakespeare