From mboxrd@z Thu Jan 1 00:00:00 1970 From: "=?ISO-8859-1?Q?Ilpo_J=E4rvinen?=" Subject: Re: Debugging TCP: Treason Uncloaked Date: Tue, 13 May 2008 14:21:18 +0300 (EEST) Message-ID: References: <482265A0.8040105@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: Netdev To: Chris Bredesen Return-path: Received: from courier.cs.helsinki.fi ([128.214.9.1]:43812 "EHLO mail.cs.helsinki.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751771AbYEMLVT (ORCPT ); Tue, 13 May 2008 07:21:19 -0400 In-Reply-To: <482265A0.8040105@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, 7 May 2008, Chris Bredesen wrote: > Hello, > > As per below thread, I'm forwarding to this list/alias. tcpdump output > is attached to the forum post. > > Thanks! > > -------- Original Message -------- > Subject: Re: F8 Treason Uncloaked > Date: Tue, 6 May 2008 20:00:51 +0100 > From: Alan Cox > Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, > Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru > a Lloegr o'r rhif cofrestru 3798903 > To: For users of Fedora > CC: cbredesen@redhat.com > References: <4820A59F.7010005@redhat.com> > > On Tue, 06 May 2008 14:38:23 -0400 > Chris Bredesen wrote: > > > Hello list, > > > > I'm trying to get this issue out to a wider audience. I posted it on the > > forum but got no responses: > > > > http://www.fedoraforum.org/forum/showthread.php?t=186331 > > > > Sorry to cross post, but I'm not sure where else to turn... > > netdev@linux.kernel.org > > but the TCP messages really indicate either a Linux bug or that the NAS > isn't talking proper TCP. Trying turning off window scaling was a good > test but beyond that tcpdump data will be needed. ...This report lacks kernel version (no I won't try to figure out what f8 or whatever is using on your box, just tell it :-)) (e.g., ...Some 2.6.25-rc had this problem). Tcp_window_scaling sysctl has nothing to do with window resizing. ...It just decides if scaling factor can be used or not. It won't guarantee you a constant window! What happened while the window was shrunk is hard to know because the log snippet doesn't have the point where the window was reduced. -- i.