From mboxrd@z Thu Jan 1 00:00:00 1970 From: Willy Tarreau Subject: Re: [PATCH] tcp: splice as many packets as possible at once Date: Mon, 19 Jan 2009 07:45:20 +0100 Message-ID: <20090119064520.GD12946@1wt.eu> References: <20090119030844.GA31941@gondor.apana.org.au> <20090118.192719.198405397.davem@davemloft.net> <20090119061420.GB12946@1wt.eu> <20090118.221908.47032075.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: herbert@gondor.apana.org.au, jarkao2@gmail.com, zbr@ioremap.net, dada1@cosmosbay.com, ben@zeus.com, mingo@elte.hu, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, jens.axboe@oracle.com To: David Miller Return-path: Received: from 1wt.eu ([62.212.114.60]:1615 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754170AbZASGpm (ORCPT ); Mon, 19 Jan 2009 01:45:42 -0500 Content-Disposition: inline In-Reply-To: <20090118.221908.47032075.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: On Sun, Jan 18, 2009 at 10:19:08PM -0800, David Miller wrote: > From: Willy Tarreau > Date: Mon, 19 Jan 2009 07:14:20 +0100 > > > On Sun, Jan 18, 2009 at 07:27:19PM -0800, David Miller wrote: > > > From: Herbert Xu > > > Date: Mon, 19 Jan 2009 14:08:44 +1100 > > > > > > > One thing to note is that Myricom's driver probably uses page > > > > frags which means that you're not actually triggering the copy. > > > > So does this mean that the corruption problem should still there for > > such a driver ? I'm asking before testing, because at these speeds, > > validity tests are not that easy ;-) > > It ought not to, but it seems that is the case where you > saw the original corruptions, so hmmm... > > Actually, I see, the myri10ge driver does put up to > 64 bytes of the initial packet into the linear area. > If the IPV4 + TCP headers are less than this, you will > hit the corruption case even with the myri10ge driver. > > So everything checks out. OK, so I will modify my tools in order to perform a few checks. Thanks! Willy