Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753624Ab2HTTLs (ORCPT ); Mon, 20 Aug 2012 15:11:48 -0400 Received: from mail-yx0-f174.google.com ([209.85.213.174]:42164 "EHLO mail-yx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752034Ab2HTTLp (ORCPT ); Mon, 20 Aug 2012 15:11:45 -0400 MIME-Version: 1.0 In-Reply-To: References: <20120816024610.GA5350@evergreen.ssec.wisc.edu> <502D42E5.7090403@redhat.com> <20120818000312.GA4262@evergreen.ssec.wisc.edu> <502F100A.1080401@redhat.com> <50321CD3.5050501@redhat.com> Date: Mon, 20 Aug 2012 12:11:43 -0700 Message-ID: Subject: Re: Repeated fork() causes SLAB to grow without bound From: Michel Lespinasse To: Rik van Riel Cc: Hugh Dickins , Daniel Forrest , Andrea Arcangeli , linux-kernel@vger.kernel.org, linux-mm@kvack.org Content-Type: text/plain; charset=ISO-8859-1 X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1015 Lines: 21 On Mon, Aug 20, 2012 at 4:53 AM, Michel Lespinasse wrote: > I wonder if it might help to add the child VMA onto the parent's > anon_vma only at the first child COW event. That way it would at least > be possible (with userspace changes) for any forking servers to > separate the areas they want to write into from the parent (such as > things that need expensive initialization), from the ones that they > want to write into from the child, and have none of the anon_vma lists > grow too large. Actually that wouldn't work. The parent's anon pages are visible from the child, so the child vma needs to be on the parent anon_vma list. Sorry for the noise :/ -- Michel "Walken" Lespinasse A program is never fully debugged until the last user dies. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/