From owner-freebsd-stable@FreeBSD.ORG Sat Apr 9 15:29:28 2011 Return-Path: Delivered-To: stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4D292106566C; Sat, 9 Apr 2011 15:29:28 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from mail-bw0-f54.google.com (mail-bw0-f54.google.com [209.85.214.54]) by mx1.freebsd.org (Postfix) with ESMTP id 9DB378FC0A; Sat, 9 Apr 2011 15:29:27 +0000 (UTC) Received: by bwz12 with SMTP id 12so4510866bwz.13 for ; Sat, 09 Apr 2011 08:29:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:message-id:date:from:user-agent :mime-version:to:cc:subject:references:in-reply-to:content-type :content-transfer-encoding; bh=Z+hK0rlVEGjbibzGp/fwaHpLFpw9rm9ffIgvlRU3an4=; b=UzxmFN8pu/ebeJU4p5rCdLO6XixopzMgMMO3DUdh6+bKWodIsQknVKWJQRSmM1gKXk h4v252FCMQDM/6/A6U/v98Fgaa9Ws1CTre2iOmatIJTrKfbid4YsXYGURxYWxKp0r7K1 4MoqtAcPkbYDRRzoTUllcajrnTXAgGvzU/PuE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=WdDGfiLKe6J8rOTzQBpuzq8gzNVIhDzU7XkUv3+9LSB65pjZLyZvoFiMR0ktXm7zBr Jvy6/vn5Xdg7Pnelkwni5eI8g/HEp5yByJuhqPVSGywpYTTBvbEpEFCZ7dS8nzEGo3uK o2I0z3eXwgRCFS2FtxQMLfzDZoluCNZlORHo0= Received: by 10.204.22.197 with SMTP id o5mr3089277bkb.68.1302362966425; Sat, 09 Apr 2011 08:29:26 -0700 (PDT) Received: from mavbook.mavhome.dp.ua (pc.mavhome.dp.ua [212.86.226.226]) by mx.google.com with ESMTPS id x6sm2218673bkv.12.2011.04.09.08.29.24 (version=SSLv3 cipher=OTHER); Sat, 09 Apr 2011 08:29:25 -0700 (PDT) Sender: Alexander Motin Message-ID: <4DA07B53.2090803@FreeBSD.org> Date: Sat, 09 Apr 2011 18:29:23 +0300 From: Alexander Motin User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.15) Gecko/20110310 Thunderbird/3.1.9 MIME-Version: 1.0 To: Bartosz Fabianowski References: <4D9EEDAF.3020803@rulez.sk> <4D9EF48C.9070907@FreeBSD.org> <4D9F2384.5000104@FreeBSD.org> <85cda6f83d328e67a552b2cd5758dbd3@rulez.sk> <4DA06F92.4070702@chillt.de> In-Reply-To: <4DA06F92.4070702@chillt.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Daniel Gerzo , stable@FreeBSD.org Subject: Re: powerd / cpufreq question X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 09 Apr 2011 15:29:28 -0000 On 09.04.2011 17:39, Bartosz Fabianowski wrote: > I just noticed this thread a day after my own fight with powerd and load > percentages that did not seem to make any sense. > > The patch I came up with is attached. It modifies powerd to use the load > percentage of the busiest core. This reduces the range of values back to > 0%...100% also for multi-core systems. While using maximum of loads can be better then using levels above 100%, it won't properly handle cases of dependent or frequently migrating threads, that are handled now with summary load and levels less then 100%. While existing powerd algorithm is indeed not perfect, it is the only relatively performance-safe, unlike others propositions. I won't argue about adding more algorithms/options to powerd, optimized for handling different situations, but I believe that default should remain safe. > On my Core i7 setup here, the change seems to work well. ... in your specific workload. And you haven't described how you measured system performance to prove that it haven't decreased. -- Alexander Motin