From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Herbert Subject: Re: [PATCH] NIU support for skb->rxhash Date: Fri, 23 Apr 2010 08:32:02 -0700 Message-ID: References: <20100422.042157.99869295.davem@davemloft.net> <1271936598.7895.5304.camel@edumazet-laptop> <20100422.141922.39169749.davem@davemloft.net> <20100423.011456.48472321.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: eric.dumazet@gmail.com, netdev@vger.kernel.org To: David Miller Return-path: Received: from smtp-out.google.com ([74.125.121.35]:40123 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757383Ab0DWPcJ convert rfc822-to-8bit (ORCPT ); Fri, 23 Apr 2010 11:32:09 -0400 Received: from hpaq12.eem.corp.google.com (hpaq12.eem.corp.google.com [10.3.21.12]) by smtp-out.google.com with ESMTP id o3NFW6QZ031173 for ; Fri, 23 Apr 2010 17:32:06 +0200 Received: from pvb32 (pvb32.prod.google.com [10.241.209.96]) by hpaq12.eem.corp.google.com with ESMTP id o3NFW25d024853 for ; Fri, 23 Apr 2010 17:32:05 +0200 Received: by pvb32 with SMTP id 32so58475pvb.4 for ; Fri, 23 Apr 2010 08:32:02 -0700 (PDT) In-Reply-To: <20100423.011456.48472321.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: > I looked into implementing this and it doesn't work. =A0The > problem is GRO want's to look into the packet very early > and we want to batch GRO a set of packets into a big packet > before shooting them over to a remote cpu. > Can you reconsider? :-) The majority of our servers see packet loads which don't allow for much batching (a lot of small RPC messages), so for those GRO is mostly unnecessary overhead and mechanisms that improve unbatched packet performance are compelling. Also, if a device already does LRO, I don't see that GRO could add a lot of value anyway. Tom > This reminds me that we can start using ->rxhash as a quick > mismatch check in the GRO flow matcher. > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html >