From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932404AbVHYAOY (ORCPT ); Wed, 24 Aug 2005 20:14:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932416AbVHYAOY (ORCPT ); Wed, 24 Aug 2005 20:14:24 -0400 Received: from smtp207.mail.sc5.yahoo.com ([216.136.129.97]:25493 "HELO smtp207.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S932404AbVHYAOX (ORCPT ); Wed, 24 Aug 2005 20:14:23 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=0wzVYFDVnAmQvI/tW+QAl5dkQKeKPVuJLsCUrh5VF6lpjP2JCzy2XGDRe086Zv+wCf4jeKa+WuGLRtaqtNp4meCHtxE+i07tlyGHC/zrcHYxA1jR0drDmk1pGToRFcXonw0uXqnFAE9Vqb2fNgppU60wa7/yGUWhTmE9KxavLKc= ; Message-ID: <430D0D6B.100@yahoo.com.au> Date: Thu, 25 Aug 2005 10:14:35 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050513 Debian/1.7.8-1 X-Accept-Language: en MIME-Version: 1.0 To: Ray Fucillo CC: linux-kernel@vger.kernel.org Subject: Re: process creation time increases linearly with shmem References: <430CBFD1.7020101@intersystems.com> In-Reply-To: <430CBFD1.7020101@intersystems.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ray Fucillo wrote: > I am seeing process creation time increase linearly with the size of the > shared memory segment that the parent touches. The attached forktest.c > is a very simple user program that illustrates this behavior, which I > have tested on various kernel versions from 2.4 through 2.6. Is this a > known issue, and is it solvable? > fork() can be changed so as not to set up page tables for MAP_SHARED mappings. I think that has other tradeoffs like initially causing several unavoidable faults reading libraries and program text. What kind of application are you using? -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com