From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: TCP and reordering Date: Wed, 28 Nov 2012 03:02:32 -0800 Message-ID: <1354100552.14302.78.camel@edumazet-glaptop> References: <50B4F2DA.8020206@hp.com> <20121127.210611.1127622873924794001.davem@davemloft.net> <1354089566.21562.20.camel@shinybook.infradead.org> <1354093703.21562.23.camel@shinybook.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Vijay Subramanian , David Miller , saku@ytti.fi, rick.jones2@hp.com, netdev@vger.kernel.org To: David Woodhouse Return-path: Received: from mail-ie0-f174.google.com ([209.85.223.174]:36899 "EHLO mail-ie0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753591Ab2K1LCf (ORCPT ); Wed, 28 Nov 2012 06:02:35 -0500 Received: by mail-ie0-f174.google.com with SMTP id k11so9832930iea.19 for ; Wed, 28 Nov 2012 03:02:35 -0800 (PST) In-Reply-To: <1354093703.21562.23.camel@shinybook.infradead.org> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, 2012-11-28 at 09:08 +0000, David Woodhouse wrote: > On Wed, 2012-11-28 at 00:22 -0800, Vijay Subramanian wrote: > > > > I don't believe reordering is tracked on the receiver side but on the > > sender, there are SNMB_MIB items. > > They can be tracked and can be viewed using nstat/netstat > > > > # nstat -az | grep -i reorder > > TcpExtTCPFACKReorder 0 0.0 > > TcpExtTCPSACKReorder 0 0.0 > > TcpExtTCPRenoReorder 0 0.0 > > TcpExtTCPTSReorder 0 0.0 > > Thanks. For me after a 64MiB download, I have an increase of one FACK, > one SACK and one TS reorder. So my connection probably does even less > reordering than I thought, and thus isn't particularly relevant to this > conversation. I'll shut up now and go back to playing with ATM. But you are the receiver. A receiver should not increase these counters.