From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rick Jones Subject: Re: ixgbe patch to provide NIC's tx/rx counters via ethtool Date: Thu, 24 Sep 2009 09:30:43 -0700 Message-ID: <4ABB9EB3.1000307@hp.com> References: <4ABAA2D0.4030608@candelatech.com> <4ABAB727.2020507@hp.com> <4ABAD48C.9010808@candelatech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: NetDev To: Ben Greear Return-path: Received: from g1t0027.austin.hp.com ([15.216.28.34]:19702 "EHLO g1t0027.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752570AbZIXQam (ORCPT ); Thu, 24 Sep 2009 12:30:42 -0400 In-Reply-To: <4ABAD48C.9010808@candelatech.com> Sender: netdev-owner@vger.kernel.org List-ID: Ben Greear wrote: > Rick Jones wrote: >> Ben Greear wrote: >> >>> When LRO is enabled, the received packet and byte counters represent the >>> LRO'd packets, not the packets/bytes on the wire. >> >> >> When LRO is enabled, are all the bytes on the wire actually >> transferred into the host? > > No...the ethernet, IP and TCP headers and such are not, for packets that > are combined into a single large SKB. > > That is why the driver counts them wrong. The bytes are off by a few > percentage points, but the packet count is off by an order of magnitude. An overly philosphical question perhaps, but are ethtool stats supposed to represent what was on the wire, or what entered the host? rick