From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Duponcheel Subject: Re: r8169/r8168 slow internet upload Date: Tue, 24 Jun 2014 00:46:14 +0200 Message-ID: <20140623224614.GA31154@offline.be> References: <20140511231946.GA12504@offline.be> Reply-To: Marc Duponcheel Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Marc Duponcheel To: netdev@vger.kernel.org Return-path: Received: from server.offline.be ([79.132.231.86]:43544 "EHLO mail.offline.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752475AbaFWXFH (ORCPT ); Mon, 23 Jun 2014 19:05:07 -0400 Content-Disposition: inline In-Reply-To: <20140511231946.GA12504@offline.be> Sender: netdev-owner@vger.kernel.org List-ID: FYI it seems upgrade to 3.14.5 -> 3.15.1 fixed issue ... not sure which change implements fix but, in any case: THANKS On 2014 May 12, Marc Duponcheel wrote: > Hi all > > I have an issue with linux box acting as router (in fact forwarder) > with 2 Realtek RTL8111/8168/8411 cards. > > In short: large file uploads are way too slow and, during such > uploads, I see TcpRetransSegs and TcpOutRsts on sending host. > > System is bleeding edge gentoo. > > I replaced linux r8169 by vendor r8168 driver. That improved some > uploads (see below). > > > - Details > -------- > > Setup is as follows (VDSL2) with down/up 50Mbps/6Mbps > > > intranet - server - router - modem - internet > > > modem = > b-box3 technicolor box in bridge mode > > router = > The linux box in question doing pppoe on eth towards internet (where > it receives an address for p-t-p to next hop) and having public /30 > network on eth towards intranet. > > server = > Also a bleeding edge gentoo gentoo box having one public address from > the /30 network (router has the other one) and the doing NAT to > devices on intranet. > > ** note ** > > Before having the [router - modem] combo, I used a CISCO886VA-K9 box > and I had expected 50/6 throughput. But provider, who migrates to > VDSL2 vectoring, does not allow cisco on its network so I use b-box3 > as bridge (the box they allow) and put a linux router behind. > > > - Symptoms > --------- > > I test ftp between my server and clients few or several hops away. > > * r8169: > > Incoming speed is OK (50Mbps) but outgoing is only 200Kbps. 30 times > too slow. > > Now I set eth speeds to 100Mbps (on linux-router, I never touch > linux-server who works fine anyway for years with cisco-router): > > Outgoing speed to few hops away is 2Mbps and to many hops away still 200Kbps. > > * replace r8169 with r8168: > > Outgoing to few hops away is 3Mbps and to many hops away is 1.5Mbps. > > As said I always notice TcpRetransSegs and TcpOutRsts on server. I > use > # watch -n 5 'nstat | grep ^Tcp' > to inspect. > > > I see few (really few) router drops on eth Rx towards intranet. In > fact I am not sure if those increase during upload. > > > If I increase txqueuelen from 1000 to 10000 on router and flush tcp > metrics on router and server, outgoing speed starts 6Mbps but soon > drops back to steady 3Mbps and 1.5Mbps. I reverted back to 1000. > > FYI: ookla speedtests on all hosts show 50/6 (only with with r8168 on > router), and, perhaps, for most work, everything is fine, but large > file uploads, in particular from our ftp server to internet many > hops away, is still 4 times too slow. > > If I do > watch 'ethtool --statistics iface | grep -v ' 0'' > on both router ethernets and server ethernet towards internet, I do not see > any error count increase. > > Note that realtek driver does not support setting eth flow control so > I could not try to turn it off (not that I expect it to help). > > Also PPP MTU/MRU are 1492 and TCPMSS clamp to PMTU is on server and router > (but that did not matter). > > - Conclusions > ------------ > > Setup is both driver and eth-speed sensitive. I also suspect TCP to > kick in to compensate for whatever issues. > > > - Questions > ---------- > > Am I missing something obvious? Or are the RTL8111/8168/8411 > cards/drivers not good for this setup? Any other hints? I am happy to > do whatever tests and provide whatever outputs that may help drive > discussion. > > > *** thanks **** -- Marc Duponcheel Velodroomstraat 74 - 2600 Berchem - Belgium +32 (0)478 68.10.91 - marc@offline.be