From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261751AbUL0Ed0 (ORCPT ); Sun, 26 Dec 2004 23:33:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261749AbUL0Ed0 (ORCPT ); Sun, 26 Dec 2004 23:33:26 -0500 Received: from fsmlabs.com ([168.103.115.128]:43477 "EHLO fsmlabs.com") by vger.kernel.org with ESMTP id S261737AbUL0EdV (ORCPT ); Sun, 26 Dec 2004 23:33:21 -0500 Date: Sun, 26 Dec 2004 21:33:05 -0700 (MST) From: Zwane Mwaikambo To: Ingo Oeser cc: linux-kernel@vger.kernel.org, Florian Weimer , Linus Torvalds , 7eggert@gmx.de, Christoph Lameter , akpm@osdl.org, linux-ia64@vger.kernel.org, linux-mm@kvack.org Subject: Re: Prezeroing V2 [3/4]: Add support for ZEROED and NOT_ZEROED free maps In-Reply-To: <200412270237.53368.ioe-lkml@rameria.de> Message-ID: References: <87llbk63sn.fsf@deneb.enyo.de> <200412270237.53368.ioe-lkml@rameria.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 27 Dec 2004, Ingo Oeser wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On Monday 27 December 2004 00:24, Florian Weimer wrote: > > By the way, some crazy idea that occurred to me: What about > > incrementally scrubbing a page which has been assigned previously to > > this CPU, while spinning inside spinlocks (or busy-waiting somewhere > > else)? > > Crazy idea, indeed. spinlocks are like safety belts: You should > actually not need them in the normal case, but they will save your butt > and you'll be glad you have them, when they actually trigger. > > So if you are making serious progress here, you have just uncovered > a spinlockcontention problem in the kernel ;-) You'd also be evicting the cache contents thus making the lock contention case even worse.