From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757032AbYA0GDA (ORCPT ); Sun, 27 Jan 2008 01:03:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755771AbYA0GCQ (ORCPT ); Sun, 27 Jan 2008 01:02:16 -0500 Received: from smtp2.linux-foundation.org ([207.189.120.14]:39765 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750869AbYA0GCO (ORCPT ); Sun, 27 Jan 2008 01:02:14 -0500 Date: Sat, 26 Jan 2008 22:00:51 -0800 From: Andrew Morton To: Michael Monnerie Cc: netatalk-admins@lists.sourceforge.net, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: netatalk slow after system upgrade (possibly kernel problem?) Message-Id: <20080126220051.d753266b.akpm@linux-foundation.org> In-Reply-To: <200801251255.48105@zmi.at> References: <200801251255.48105@zmi.at> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.19; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (cc netdev) > On Fri, 25 Jan 2008 12:55:42 +0100 Michael Monnerie wrote: > Dear lists, > > I've been spending a LOT of time trying to find out where's the problem, > but can't find it and therefore seek urgent help now. We have the > following system: > > Server with VMware server > -> VM running a webserver and netatalk > -> 2 other VMs not related > > The VM with netatalk was SUSE 10.0 with kernel 2.6.13-15.15-smp (from > SUSE), and things were pretty fun and quick. Then we upgraded to SUSE > 10.2 and now 10.3, where everything EXCEPT netatalk runs perfect. Since > this upgrade, Apple clients (MacOS X) now do READ very very slowly > (about 512KB/s over the gigabit LAN), while writing to the server still > is normal (>20MB/s). I've even retried with the newest kernel > 2.6.23.13, tried different /proc/sys/net/ipv4/tcp_congestion_control > (cubic, reno, bic, etc.) and nothing helps. I've then tried to install > Samba and found that we have similar problems reading with it from > MacOS clients. Now I'm pretty sure it should be something with the > linux kernel, but I don't understand what. > > Here are the wireshark dumps in pcap format: > http://zmi.at/x/atalk-write-fast.pcap > -> you can see writing to the server (192.168.120.9) is normal and fast > > http://zmi.at/x/atalk-read-slow.pcap > -> reading is horribly slow. Lots of "unknown", because of netatalk or > what? > > http://zmi.at/x/unknown-atalk.pcap > -> another dump while reading, you see "unknown" reads. I'm not sure if > it's just wireshark not understanding the packets or netatalk. > > And trying with samba: > http://zmi.at/x/smb-read-slow.pcap > http://zmi.at/x/smb-write-quick.pcap > you can see that it's also slow. > > Now why did it work with the old 2.6.13 kernel? I still have that old > VM, and when I start it, it is always perfectly fast. Only newer > versions are slow. Can somebody give me a hint please? It would be interesting if this could be repeated on bare hardware, so we can eliminate the possibility that it is some weird interaction with vmware.