From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757292AbZILCYh (ORCPT ); Fri, 11 Sep 2009 22:24:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757227AbZILCYg (ORCPT ); Fri, 11 Sep 2009 22:24:36 -0400 Received: from qw-out-2122.google.com ([74.125.92.27]:43673 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755908AbZILCYf (ORCPT ); Fri, 11 Sep 2009 22:24:35 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; b=ZRYovqG8p9ALd6zB5pIe2qL/+HIyngtltYX82y4SPQtEUCnvn2Gy3PMRqoG+3WT2lp 22wCznxCPBjqhAP/47lXozQy28g++747/vPaFiBl/GSqZetlxQ7jx0qGWGNizbM8qx4X yBNshFLLvf7WYdiwbPWWjOWh7HOaqsfFmlWbo= MIME-Version: 1.0 In-Reply-To: References: <20090911192505.GA20006@elte.hu> Date: Fri, 11 Sep 2009 19:24:38 -0700 X-Google-Sender-Auth: 0719dad730c9a118 Message-ID: <12c511ca0909111924s42d000dsbf378009d9434ddc@mail.gmail.com> Subject: Re: [GIT PULL] sched/core for v2.6.32 From: Tony Luck To: Jesper Juhl Cc: Linus Torvalds , Ingo Molnar , linux-kernel@vger.kernel.org, Peter Zijlstra , Mike Galbraith Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 11, 2009 at 4:34 PM, Jesper Juhl wrote: > That may be so; but most people I've ever talked to about multiple > processes, fork, vfork and the like, have mostly assumed child-runs-first. > That is just my personal experience. > So I get worried when that assumption is made false. With multi-core cpus becoming (being?) the norm, almost all systems are SMP now. So child and parent can surely end up running in parallel very often. So applications that make assumptions about child running first are going to be frequently surprised. Aren't they? -Tony