From owner-freebsd-stable@FreeBSD.ORG Sat Dec 17 21:13:30 2011 Return-Path: Delivered-To: freebsd-stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B2D49106566C for ; Sat, 17 Dec 2011 21:13:30 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id B96A78FC13 for ; Sat, 17 Dec 2011 21:13:29 +0000 (UTC) Received: from porto.starpoint.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id XAA09521; Sat, 17 Dec 2011 23:13:18 +0200 (EET) (envelope-from avg@FreeBSD.org) Received: from localhost ([127.0.0.1]) by porto.starpoint.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1Rc1ZG-0009tX-Fh; Sat, 17 Dec 2011 23:13:18 +0200 Message-ID: <4EED05EC.8050103@FreeBSD.org> Date: Sat, 17 Dec 2011 23:13:16 +0200 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:8.0) Gecko/20111206 Thunderbird/8.0 MIME-Version: 1.0 To: George Mitchell References: <4EE1EAFE.3070408@m5p.com> <4EE2AE64.9060802@m5p.com> <4EE88343.2050302@m5p.com> <4EE933C6.4020209@zedat.fu-berlin.de> <4EECD261.2080208@m5p.com> In-Reply-To: <4EECD261.2080208@m5p.com> X-Enigmail-Version: undefined Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-stable@FreeBSD.org, Oliver Pinter Subject: Re: SCHED_ULE should not be the default 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, 17 Dec 2011 21:13:30 -0000 on 17/12/2011 19:33 George Mitchell said the following: > Summing up for the record, in my original test: > 1. It doesn't matter whether X is running or not. > 2. The problem is not limited to two or fewer CPUs. (It also happens > for me on a six-CPU system.) > 3. It doesn't require nCPU + 1 compute-bound processes, just nCPU. > > With nCPU compute-bound processes running, with SCHED_ULE, any other > process that is interactive (which to me means frequently waiting for > I/O) gets ABYSMAL performance -- over an order of magnitude worse than > it gets with SCHED_4BSD under the same conditions. I definitely do not see anything like this. Specifically: - with X - with 2 CPUs - with nCPU and/or nCPU + 1 compute-bound processes - with SCHED_ULE obviously :-) I do not get "abysmal" performance for I/O active tasks. Perhaps there is something specific that you would want me to run and measure. -- Andriy Gapon