Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755297AbZJ2PXv (ORCPT ); Thu, 29 Oct 2009 11:23:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754928AbZJ2PXv (ORCPT ); Thu, 29 Oct 2009 11:23:51 -0400 Received: from mail-out2.uio.no ([129.240.10.58]:41262 "EHLO mail-out2.uio.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754402AbZJ2PXu (ORCPT ); Thu, 29 Oct 2009 11:23:50 -0400 Message-ID: <879da81bfa8a9f0f34717c64b08332ed.squirrel@webmail.uio.no> Date: Thu, 29 Oct 2009 16:23:53 +0100 Subject: Re: [PATCH 3/3] net: TCP thin dupack From: apetlund@simula.no To: Ilpo =?iso-8859-1?Q?J=E4rvinen?= Cc: "Andreas Petlund" , "Netdev" , "LKML" , shemminger@vyatta.com, "David Miller" User-Agent: SquirrelMail/1.4.19 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-UiO-Ratelimit-Test: rcpts/h 20 msgs/h 3 sum rcpts/h 31 sum msgs/h 5 total rcpts 424 max rcpts/h 37 ratelimit 0 X-UiO-Spam-info: not spam, SpamAssassin (score=-5.0, required=5.0, autolearn=disabled, UIO_MAIL_IS_INTERNAL=-5, uiobl=NO, uiouri=NO) X-UiO-Scanned: 3DA9E59205CACD7CB47ECEC965B14F322C152F1C X-UiO-SPAM-Test: remote_host: 129.240.4.214 spam_score: -49 maxlevel 80 minaction 1 bait 0 mail/h: 190 total 1919867 max/h 678 blacklist 0 greylist 0 ratelimit 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1692 Lines: 48 I apologise that some of you received this mail more than once. My email client played a HTML-trick on me. >> + /* If a thin stream is detected, retransmit after first >> + * received dupack */ >> + if ((tp->thin_dupack || sysctl_tcp_force_thin_dupack) && >> + tcp_dupack_heurestics(tp) > 1 && tcp_stream_is_thin(tp)) >> + return 1; >> + >> return 0; >> } > > Have you tested it? ...I doubt this will work like you say and retransmit > something when the window is small. ...Besides, you should have built this > patch on top of the function rename you submitted earlier as after DaveM applied that this will no longer even compile... > > -- > i. > We have performed extensive tests mapping the effect of the patch you commented on some months ago. Since then, the only change was the one you requested of switching tcp_fackets_out() with tcp_dupack_heurestics(). After inspecting the code, I believed the effect should be equal to the previous, only making considerations for SACK and FACK availability. Please tell if this will break the intended effect, and I will modify the patch accordingly. Graphs from our tests of the original patch can be found at the location linked to below. I have tested the new one for functionality, but have not et performed tests on this scope as the changes were minor. I will, of course, fix the function rename in the next iteration. Sorry for that. http://folk.uio.no/apetlund/lktmp/ -AP -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/