From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751899Ab0IMJPw (ORCPT ); Mon, 13 Sep 2010 05:15:52 -0400 Received: from mailout-de.gmx.net ([213.165.64.22]:60322 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with SMTP id S1750970Ab0IMJPv (ORCPT ); Mon, 13 Sep 2010 05:15:51 -0400 X-Authenticated: #14349625 X-Provags-ID: V01U2FsdGVkX1+xQxpaKIaxn0EG3S+kjjv0eUhxuVm8JPp8Kyt7rK FOWEVQAHlnD6Ek Subject: Re: [RFC patch 1/2] sched: dynamically adapt granularity with nr_running From: Mike Galbraith To: Peter Zijlstra Cc: Ingo Molnar , Mathieu Desnoyers , LKML , Linus Torvalds , Andrew Morton , Steven Rostedt , Thomas Gleixner , Tony Lindgren In-Reply-To: <1284366936.2275.27.camel@laptop> References: <20100911173732.551632040@efficios.com> <20100911174003.051303123@efficios.com> <20100912061452.GA3383@elte.hu> <1284276098.9111.24.camel@marge.simson.net> <20100912181626.GB32327@Krystal> <1284351183.7321.36.camel@marge.simson.net> <20100913064153.GB14728@elte.hu> <1284361716.25120.19.camel@marge.simson.net> <1284366936.2275.27.camel@laptop> Content-Type: text/plain; charset="UTF-8" Date: Mon, 13 Sep 2010 11:16:13 +0200 Message-Id: <1284369373.14710.11.camel@marge.simson.net> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1.1 Content-Transfer-Encoding: 8bit X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2010-09-13 at 10:35 +0200, Peter Zijlstra wrote: > On Mon, 2010-09-13 at 09:08 +0200, Mike Galbraith wrote: > > We need a better fork fairness gizmo. > > Proper zero-lag insertion would do. Much sadness in that tracking that > costs a u64 mult per enqueu/dequeue and using it adds a s64 div. (math _sucks_:) > But if you want, have a play with: maximum latency: 48475.3 µs average latency: 6881.4 µs missed timer events: 0 Darn. make -j3 is gaining a tad over a hog as well, roughly the same as turning START_DEBIT off. -Mike