From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031474AbXEDSE7 (ORCPT ); Fri, 4 May 2007 14:04:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1031470AbXEDSE7 (ORCPT ); Fri, 4 May 2007 14:04:59 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:46198 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1031425AbXEDSE5 (ORCPT ); Fri, 4 May 2007 14:04:57 -0400 Date: Fri, 4 May 2007 11:04:55 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Peter Zijlstra cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, Trond Myklebust , Thomas Graf , David Miller , James Bottomley , Mike Christie , Andrew Morton , Daniel Phillips , Pekka Enberg Subject: Re: [PATCH 08/40] mm: kmem_cache_objsize In-Reply-To: <1178301545.24217.56.camel@twins> Message-ID: References: <20070504102651.923946304@chello.nl> <20070504103157.215424767@chello.nl> <1178301545.24217.56.camel@twins> 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 Fri, 4 May 2007, Peter Zijlstra wrote: > > I could add a function that tells you how many object you could allocate > > from a slab without the page allocator becoming involved? It would count > > the object slots available on the partial slabs. > > I need to know how many pages to reserve to allocate a given number of > items from a given slab; assuming the partial slabs are empty. That is, > I need a worst case upper bound. Ok so you really need the number of objects per page? If you know the number of objects then you can calculate the pages needed which would be the maximum memory needed?