On Tue, May 26, 2015 at 12:42:50PM +0200, Petter Adsen wrote: > On Sun, 24 May 2015 16:01:41 +0300 > Reco <recovery...@gmail.com> wrote: > > > Hi. > > > > On Sun, 24 May 2015 13:47:48 +0200 > > Petter Adsen <pet...@synth.no> wrote: > > > > > On Sun, 24 May 2015 13:26:52 +0200 > > > Petter Adsen <pet...@synth.no> wrote: > > > > Thanks to you, I now get ~880Mbps, which is a lot better. It seems > > > > increasing the MTU was what had the most effect, so I won't bother > > > > with TCP window size. > > > > > > Now, this is a little odd: > > > > > > petter@monster:/etc$ iperf -i 1 -c fenris -r > > > ------------------------------------------------------------ > > > Server listening on TCP port 5001 > > > TCP window size: 85.3 KByte (default) > > > ------------------------------------------------------------ > > > ------------------------------------------------------------ > > > Client connecting to fenris, TCP port 5001 > > > TCP window size: 280 KByte (default) > > > ------------------------------------------------------------ > > > [ 5] local 192.168.0.105 port 49636 connected with 192.168.0.103 > > > port 5001 [ ID] Interval Transfer Bandwidth > > > [ 5] 0.0- 1.0 sec 104 MBytes 875 Mbits/sec > > > [ 5] 1.0- 2.0 sec 97.8 MBytes 820 Mbits/sec > > > [ 5] 2.0- 3.0 sec 104 MBytes 868 Mbits/sec > > > [ 5] 3.0- 4.0 sec 104 MBytes 876 Mbits/sec > > > [ 5] 4.0- 5.0 sec 104 MBytes 876 Mbits/sec > > > [ 5] 5.0- 6.0 sec 83.0 MBytes 696 Mbits/sec > > > [ 5] 6.0- 7.0 sec 105 MBytes 879 Mbits/sec > > > [ 5] 7.0- 8.0 sec 104 MBytes 875 Mbits/sec > > > [ 5] 8.0- 9.0 sec 105 MBytes 884 Mbits/sec > > > [ 5] 9.0-10.0 sec 104 MBytes 877 Mbits/sec > > > [ 5] 0.0-10.0 sec 1016 MBytes 852 Mbits/sec > > > [ 4] local 192.168.0.105 port 5001 connected with 192.168.0.103 > > > port 34815 [ 4] 0.0- 1.0 sec 98.5 MBytes 826 Mbits/sec > > > [ 4] 1.0- 2.0 sec 98.5 MBytes 826 Mbits/sec > > > [ 4] 2.0- 3.0 sec 97.4 MBytes 817 Mbits/sec > > > [ 4] 3.0- 4.0 sec 98.0 MBytes 822 Mbits/sec > > > [ 4] 4.0- 5.0 sec 98.5 MBytes 827 Mbits/sec > > > [ 4] 5.0- 6.0 sec 98.1 MBytes 823 Mbits/sec > > > [ 4] 6.0- 7.0 sec 98.6 MBytes 827 Mbits/sec > > > [ 4] 7.0- 8.0 sec 98.5 MBytes 826 Mbits/sec > > > [ 4] 8.0- 9.0 sec 98.5 MBytes 827 Mbits/sec > > > [ 4] 9.0-10.0 sec 98.5 MBytes 826 Mbits/sec > > > [ 4] 0.0-10.0 sec 984 MBytes 825 Mbits/sec > > > > > > I have run it many times, and the results are consistently ~50Mbps > > > lower in the other direction. MTU is set to 7152 on both hosts, but > > > the window size is back to the default values (212992). > > > > Hmm. A first thought is that you have a different TCP window size on > > client and a server. > > Nope. Exactly the same. > > > And a second thought is that you probably should check interface > > statistics with ifconfig or 'ip -s link show'. Every packet that is > > not RX or TX means trouble. > > Clean. On both hosts.
I'm out of ideas then, sorry. > And even worse, after starting to mess with this, browsing is > _abysmal_. After taking a few speed tests online (speed.io etc), > upload/download and ping times seem good, but the number of connections > per minute are severely limited, hovering at ~700. A friend on the same > network, just down the street and with the same connection gets over > 1800. We are connected to the same node. Whether these tests are > trustworthy, though, I have no idea. And that means jumbo frames bit you. Don't worry, good old iproute comes to the rescue. A start state of non-router host (I'm assuming that eth0 has MTU > 1500): # ip ro l default via 192.168.32.1 dev eth0 metric 303 192.168.32.0/20 dev eth0 proto kernel scope link src 192.168.32.227 metric 303 Needed changes: # ip ro d default # ip ro a default via 192.168.32.1 dev eth0 mtu 1500 So, you keep non-standard MTU for your network, but set standard MTU for outside world. An example assumes that 192.168.32.0/20 is an internal network and 192.168.32.1 is a router. The implementation I'd use is a post-up script in /etc/network/interfaces. I'm not that familiar with DHCP so I cannot comment if it's possible to advertise different MTUs on different routes. > I've tried to set everything back to the defaults, as I've documented > every change I've made, but it doesn't seem to help. I'll try to reboot > later today if I can, I have so much context up right now that I really > don't want to lose, but I haven't made any permanent changes yet, so it > should come up the way it was. May I suggest using etckeeper for this? The tool is invaluable if one needs to answer a question such as "what exactly did I changed a couple of days ago?". The usual caveat is that using etckeeper requires at least casual knowledge of any RCS that's supported by etckeeper (I prefer git for this). Reco -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/20150526151520.GA30331@x101h
