From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx185.postini.com [74.125.245.185]) by kanga.kvack.org (Postfix) with SMTP id 93F986B004D for ; Wed, 21 Mar 2012 14:05:23 -0400 (EDT) Received: by pbcup15 with SMTP id up15so1226907pbc.14 for ; Wed, 21 Mar 2012 11:05:22 -0700 (PDT) Subject: Re: Patch workqueue: create new slab cache instead of hacking From: Eric Dumazet In-Reply-To: References: <1332238884-6237-1-git-send-email-laijs@cn.fujitsu.com> <1332238884-6237-7-git-send-email-laijs@cn.fujitsu.com> <20120320154619.GA5684@google.com> <4F6944D9.5090002@cn.fujitsu.com> <1332341381.7893.17.camel@edumazet-glaptop> <1332345859.5330.8.camel@edumazet-glaptop> Content-Type: text/plain; charset="UTF-8" Date: Wed, 21 Mar 2012 11:05:19 -0700 Message-ID: <1332353119.9433.2.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter Cc: Tejun Heo , Lai Jiangshan , Pekka Enberg , Matt Mackall , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org On Wed, 2012-03-21 at 12:54 -0500, Christoph Lameter wrote: > On Wed, 21 Mar 2012, Eric Dumazet wrote: > > > On Wed, 2012-03-21 at 10:03 -0500, Christoph Lameter wrote: > > > On Wed, 21 Mar 2012, Eric Dumazet wrote: > > > > > > > Creating a dedicated cache for few objects ? Thats a lot of overhead, at > > > > least for SLAB (no merges of caches) > > > > > > Its some overhead for SLAB (a lot is what? If you tune down the per cpu > > > caches it should be a couple of pages) but its none for SLUB. > > > > SLAB overhead per cache is O(CPUS * nr_node_ids) (unless alien caches > > are disabled) > > nr_node_ids==2 in the standard case these days. Alien caches are minimal. Thats not true. Some machines use lots of nodes (fake nodes) for various reasons. And they cant disable alien caches for performance reasons. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org