From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Greear Subject: Re: Why is LRO off by default on ixgbe? Date: Fri, 25 Sep 2009 14:53:48 -0700 Message-ID: <4ABD3BEC.8040006@candelatech.com> References: <4ABA57D1.5000905@candelatech.com> <20090925213727.GA3291@gondor.apana.org.au> <20090925214303.GA3399@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: shemminger@vyatta.com, netdev@vger.kernel.org To: Herbert Xu Return-path: Received: from mail.candelatech.com ([208.74.158.172]:58414 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751823AbZIYVzq (ORCPT ); Fri, 25 Sep 2009 17:55:46 -0400 In-Reply-To: <20090925214303.GA3399@gondor.apana.org.au> Sender: netdev-owner@vger.kernel.org List-ID: On 09/25/2009 02:43 PM, Herbert Xu wrote: > On Fri, Sep 25, 2009 at 02:37:27PM -0700, Herbert Xu wrote: >> >>> Ok. It seems GRO was enabled the whole time, but LRO is what gave me the >>> extra performance boost. >>> >>> In this particular case, I'm not actually routing, though I do have ip-forward >>> enabled, so I guess LRO will be OK as long as I'm careful... >> >> What? A driver is either GRO or LRO, it can't be both. What >> kernel version was this? > > Oh perhaps you mean LRO performed by hardware? That would make > sense indeed. It's also one of the reasons why we hope the hardware > folks would switch over to GRO so we can enable it for everyone :) I assume it's in hardware. I am using ixgbe driver, 82599 chipset, 2.6.31 kernel. GRO was showing as enabled the whole time in ethtool. Turning on LRO gave me an extra 6Gbps (from 12Gbps -> 18Gbps) receive throughput, so it certainly had some affect! Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com