Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753681AbYJGOTx (ORCPT ); Tue, 7 Oct 2008 10:19:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753195AbYJGOTm (ORCPT ); Tue, 7 Oct 2008 10:19:42 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:55374 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751426AbYJGOTl (ORCPT ); Tue, 7 Oct 2008 10:19:41 -0400 Message-ID: <48EB6F2D.100@linux-foundation.org> Date: Tue, 07 Oct 2008 09:16:13 -0500 From: Christoph Lameter User-Agent: Thunderbird 2.0.0.17 (Windows/20080914) MIME-Version: 1.0 To: Evgeniy Polyakov CC: Corey Minyard , David Miller , dada1@cosmosbay.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, shemminger@vyatta.com, paulmck@linux.vnet.ibm.com Subject: Re: [PATCH 3/3] Convert the UDP hash lock to RCU References: <20081006185026.GA10383@minyard.local> <48EA8197.6080502@cosmosbay.com> <20081006.144002.56418911.davem@davemloft.net> <48EA9A59.1090306@acm.org> <20081007083750.GB17079@2ka.mipt.ru> In-Reply-To: <20081007083750.GB17079@2ka.mipt.ru> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 693 Lines: 16 Evgeniy Polyakov wrote: > On Mon, Oct 06, 2008 at 06:08:09PM -0500, Corey Minyard (minyard@acm.org) wrote: >> Would using SLAB_DESTROY_BY_RCU be ok, or would that be too expensive? > > I tested skb destruction via RCU path, and got 2.5 times worse numbers > with small-packets-bulk-transfer workload. Was this with regular RCU freeing? This will cool down the cacheline before frees. You need SLAB_DESTROY_BY_RCU to keep the objects cache hot. -- 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/