From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 21 Sep 2001 09:01:42 -0300 (BRST) From: Rik van Riel Subject: Re: broken VM in 2.4.10-pre9 In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: "Eric W. Biederman" Cc: Alan Cox , Daniel Phillips , Rob Fuller , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On 21 Sep 2001, Eric W. Biederman wrote: > Swapping is an important case. But 9 times out of 10 you are managing > memory in caches, and throwing unused pages into swap. You aren't > busily paging the data back an forth. But if I have to make a choice > in what kind of situation I want to take a performance hit, paging > approaching thrashing or a system whose working set size is well > within RAM. I'd rather take the hit in the system that is paging. > Besides I also like to run a lot of shell scripts, which again stress > the fork()/exec()/exit() path. > > So no I don't think keeping those paths fast is silly. Absolutely agreed. Ben and I have already been thinking a bit about memory objects, so we have both reverse mappings AND we can skip copying the page tables at fork() time (needing to clear less at the subsequent exec(), too) ... Of course this means I'll throw away my pte-based reverse mapping code and will look at an object-based reverse mapping scheme like Ben made for 2.1 and DaveM made for 2.3 ;) regards, Rik -- IA64: a worthy successor to i860. http://www.surriel.com/ http://distro.conectiva.com/ Send all your spam to aardvark@nl.linux.org (spam digging piggy) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/