Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964798AbWA0AWD (ORCPT ); Thu, 26 Jan 2006 19:22:03 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964817AbWA0AWB (ORCPT ); Thu, 26 Jan 2006 19:22:01 -0500 Received: from omx1-ext.sgi.com ([192.48.179.11]:34539 "EHLO omx1.americas.sgi.com") by vger.kernel.org with ESMTP id S964798AbWA0AWA (ORCPT ); Thu, 26 Jan 2006 19:22:00 -0500 Date: Thu, 26 Jan 2006 16:21:43 -0800 (PST) From: Christoph Lameter To: Matthew Dobson cc: linux-kernel@vger.kernel.org, sri@us.ibm.com, andrea@suse.de, pavel@suse.cz, linux-mm@kvack.org Subject: Re: [patch 3/9] mempool - Make mempools NUMA aware In-Reply-To: <43D96633.4080900@us.ibm.com> Message-ID: References: <20060125161321.647368000@localhost.localdomain> <1138233093.27293.1.camel@localhost.localdomain> <43D953C4.5020205@us.ibm.com> <43D95A2E.4020002@us.ibm.com> <43D96633.4080900@us.ibm.com> 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 Content-Length: 1387 Lines: 26 On Thu, 26 Jan 2006, Matthew Dobson wrote: > Allocations backed by a mempool must always be allocated via > mempool_alloc() (or mempool_alloc_node() in this case). What that means > is, without a mempool_alloc_node() function, NO mempool backed allocations > will be able to request a specific node, even when the system has PLENTY of > memory! This, IMO, is unacceptable. Adding more NUMA-awareness to the > mempool system allows us to keep the same slab behavior as before, as well > as leaving us free to ignore the node requests when memory is low. Ok. That makes sense. I thought the mempool_xxx functions were only for emergencies. But nevertheless you still duplicate all memory allocation functions. I already was a bit concerned when I added the _node stuff. What may be better is to add some kind of "allocation policy" to an allocation. That allocation policy could require the allocation on a node, distribution over a series of nodes, require allocation on a particular node, or allow the use of emergency pools etc. Maybe unify all the different page allocations to one call and do the same with the slab allocator. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/