From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pekka Enberg Subject: Re: [PATCH 08/40] mm: kmem_cache_objsize Date: Fri, 04 May 2007 21:41:32 +0300 Message-ID: <463B7E5C.8030201@cs.helsinki.fi> References: <20070504102651.923946304@chello.nl> <20070504103157.215424767@chello.nl> <1178301545.24217.56.camel@twins> <1178302904.2767.6.camel@lappy> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Peter Zijlstra , 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 To: Christoph Lameter Return-path: Received: from courier.cs.helsinki.fi ([128.214.9.1]:42427 "EHLO mail.cs.helsinki.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161616AbXEDSlV (ORCPT ); Fri, 4 May 2007 14:41:21 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Christoph Lameter wrote: > Hmmm... Maybe lets have > > unsigned kmem_estimate_pages(struct kmem_cache *slab_cache, int objects) > > which would calculate the worst case memory scenario for allocation the > number of indicated objects? IIRC this looks more or less what Peter had initially. I don't like the API because there's no way for slab (perhaps this is different for slub) how many pages you really need due to per-node and per-cpu caches, etc. It's better that the slab tells you what it actually knows and lets the callers figure out what a worst-case upper bound is. Pekka