From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 17 May 2007 12:24:54 -0700 (PDT) From: Christoph Lameter Subject: Re: [PATCH 0/5] make slab gfp fair In-Reply-To: <1179429499.2925.26.camel@lappy> Message-ID: References: <20070514131904.440041502@chello.nl> <1179385718.27354.17.camel@twins> <20070517175327.GX11115@waste.org> <1179429499.2925.26.camel@lappy> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Peter Zijlstra Cc: Matt Mackall , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Thomas Graf , David Miller , Andrew Morton , Daniel Phillips , Pekka Enberg List-ID: On Thu, 17 May 2007, Peter Zijlstra wrote: > The proposed patch doesn't change how the kernel functions at this > point; it just enforces an existing rule better. Well I'd say it controls the allocation failures. And that only works if one can consider the system having a single zone. Lets say the system has two cpusets A and B. A allocs from node 1 and B allocs from node 2. Two processes one in A and one in B run on the same processor. Node 1 gets very low in memory so your patch kicks in and sets up the global memory emergency situation with the reserve slab. Now the process in B will either fail although it has plenty of memory on node 2. Or it may just clear the emergency slab and then the next critical alloc of the process in A that is low on memory will fail. -- 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/ . Don't email: email@kvack.org