From mboxrd@z Thu Jan 1 00:00:00 1970 From: Satoru Moriya Subject: RE: [PATCH v2 0/2] Tracepoint for tcp retransmission Date: Mon, 6 Feb 2012 13:32:33 -0500 Message-ID: <65795E11DBF1E645A09CEC7EAEE94B9CB8E7B0F3@USINDEVS02.corp.hds.com> References: <65795E11DBF1E645A09CEC7EAEE94B9CB728DD67@USINDEVS02.corp.hds.com> <20120120.135028.1359677274445012541.davem@davemloft.net> <65795E11DBF1E645A09CEC7EAEE94B9CB8D3EA7B@USINDEVS02.corp.hds.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Cc: David Miller , "netdev@vger.kernel.org" , "nhorman@tuxdriver.com" , "tgraf@infradead.org" , "stephen.hemminger@vyatta.com" , "hagen@jauu.net" , "eric.dumazet@gmail.com" , Seiji Aguchi To: Yuchung Cheng Return-path: Received: from usindpps06.hds.com ([207.126.252.19]:58815 "EHLO usindpps06.hds.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750756Ab2BFScw convert rfc822-to-8bit (ORCPT ); Mon, 6 Feb 2012 13:32:52 -0500 In-Reply-To: Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 02/03/2012 11:40 PM, Yuchung Cheng wrote: > I totally understand that you need deeper instrumentation for *your* > business. At Google, we instrument a lot more in TCP as well. But we > have yet to upstream these changes because it's not universally useful > for default Linux kernel. I failed to see how different failures of a > TCP retransmission must be recorded and exported. Could you elaborate > your last point? Hi Yuchung, Ultimately, we'd like to record all the tcp retransmission failures but for the first step, we'd like to know whether kernel succeeded retransmission or not (kernel sent a packet or not). Does it make sense? Regards, Satoru