From owner-freebsd-current@FreeBSD.ORG Thu Dec 22 10:51:30 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B552B1065670 for ; Thu, 22 Dec 2011 10:51:30 +0000 (UTC) (envelope-from mozolevsky@gmail.com) Received: from mail-pw0-f54.google.com (mail-pw0-f54.google.com [209.85.160.54]) by mx1.freebsd.org (Postfix) with ESMTP id 8A6468FC0A for ; Thu, 22 Dec 2011 10:51:30 +0000 (UTC) Received: by pbcc3 with SMTP id c3so6675430pbc.13 for ; Thu, 22 Dec 2011 02:51:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:cc:content-type; bh=HETqwWRDaLVG6ucP6/ZVGvTa8m4KfTPo44oprZTfioo=; b=QKIq585Awi81fMFg7VgM/SRjmGKHrchSlh9/XvEVdXX8+M5DdoDcDSb33VQqbjkiGE eqTHonKRTWTTyEuUXZwkKASFenL9DIJeq4j3Bq8FUvK2ly43YoY1XYsRPL2y1QeAqBI8 Lp4O1SZs+Lqhbtapt4appKSMH2YsjP/v6RpRk= Received: by 10.68.189.2 with SMTP id ge2mr14826077pbc.63.1324551090155; Thu, 22 Dec 2011 02:51:30 -0800 (PST) MIME-Version: 1.0 Sender: mozolevsky@gmail.com Received: by 10.68.12.199 with HTTP; Thu, 22 Dec 2011 02:50:49 -0800 (PST) In-Reply-To: <4EF30290.2030600@digsys.bg> References: <4EF25468.9040204@gmail.com> <4EF2C613.3020609@digsys.bg> <4EF30290.2030600@digsys.bg> From: Igor Mozolevsky Date: Thu, 22 Dec 2011 10:50:49 +0000 X-Google-Sender-Auth: fQH8kprzixh1OtlUpgfYH0JJXbc Message-ID: To: Daniel Kalchev Content-Type: text/plain; charset=UTF-8 Cc: freebsd-current@freebsd.org Subject: Re: Benchmark (Phoronix): FreeBSD 9.0-RC2 vs. Oracle Linux 6.1 Server X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 22 Dec 2011 10:51:30 -0000 On 22 December 2011 10:12, Daniel Kalchev wrote: > As for how fast to get from point A to point B. If you observe speed limits, > that will depend only on the pilot, no? :) > Both cars are sufficiently faster than the imposed speed limits. You are ignoring acceleration, handling, and other factors... Besides, you're missing the point: *given same conditions* a benchmark allows one to show how A performs compared to B, which is why I said it is important to keep everything else constant! At the end of the day, what users, sysadmins, &c want to know is given hardware configuration H and requirement R will software X outperform software Y or Z. The components and the bells and whistles of X, Y or Z are, quite often, irrelevant (unless one has some silly idealogical reason, for example). > On very specific hardware, such as systems with many CPUs and lots of > memory, you may see one better than the other -- this in most cases will be > relevant to tuning, but also to overall system architecture. Are you saying that careful tuning will give you _orders of magnitude_ performance increase? Got numbers to back that up? ;-) > You may make an very "scientific", well documented and repeatable benchmark, > such as this one: > > time dd if=/dev/zero of=/dev/null > > .. then optimize your particular OS to run it at the highest possible > rate... and so what? Do you know what this benchmark measures? :) Yes, do you? I hope you are not being deliberately obtuse here... Besides, I would criticise your test in this example: have you tried running that with, say, bs=1g count=1000? Is there a difference how fast FreeBSD completes that vs how fast a Linux box does the same? The point of documenting a repeatable benchmark is to enable the person interpreting the results to see what was done (and verify) to achieve the result and treat that result accordingly. Cheers, -- Igor