From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: listen(2) backlog changes in or around Linux 3.1? Date: Thu, 18 Oct 2012 18:54:00 +0200 Message-ID: <1350579240.32642.62.camel@edumazet-glaptop> References: <507C4401.7050500@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: enh Return-path: Received: from mail-ea0-f174.google.com ([209.85.215.174]:49150 "EHLO mail-ea0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757162Ab2JRQyF (ORCPT ); Thu, 18 Oct 2012 12:54:05 -0400 Received: by mail-ea0-f174.google.com with SMTP id c13so2240022eaa.19 for ; Thu, 18 Oct 2012 09:54:03 -0700 (PDT) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 2012-10-16 at 16:31 -0700, enh wrote: > boiling things down to a short C++ program, i see that i can reproduce > the behavior even on 2.6 kernels. if i run this, i see 4 connections > immediately (3 + 1, as i'd expect)... but then about 10s later i see > another 2. and every few seconds after that, i see another 2. i've let > this run until i have hundreds of connect(2) calls that have returned, > despite my small listen(2) backlog and the fact that i'm not > accept(2)ing. > > so i guess the only thing that's changed with newer kernels is timing > (hell, since i only see newer kernels on newer hardware, it might just > be a hardware thing). > > and clearly i don't understand what the listen(2) backlog means any more. Hi Elliott I would say there is a bug (or several !!), and this needs a fix. I am investigating. Thanks