Bridge interface performance


#1

Hello.

I’m using VyOS 1.1.0 (Helium), installed on hardware, in a lab environment. It’s main function is that of a layer3 switch. I have two Cisco SG200-26 switches. Each cisco switch has two ports in an LACP-enabled LAG. The VyOS box has two dual-port NIC’s. In VyOS I have bond0 (GE20/21 on cisco switch 1) and bond1 (GE20/21 on cisco switch 2). I have several bridge interfaces and corresponding vif’s on both bonded interfaces. All connectivity is working, but I seem to be having performance issues with file copies between the two cisco switches with traffic on the same vlan. I’m using iPerf between two hosts for testing. I ran five, one minute tests, in each configuration and took their average to get the following numbers:

Server Client Speed

Switch1 Switch1 739 Mbits/sec
Switch2 Switch2 713 Mbits/sec

Switch1 Switch2 561 Mbits/sec
Switch2 Switch1 518 Mbits/sec


#2

Did you check CPU usage on the vyos box during the transfer ?


#3

Yep. I ran top during one of the tests and it was almost idle. As a sanity check I ran it again and it looked ok. Here’s the summary lines from about half way through another 5x 1 minute test.

top - 12:17:50 up 16:53, 1 user, load average: 0.09, 0.10, 0.07
Tasks: 82 total, 1 running, 80 sleeping, 0 stopped, 1 zombie
Cpu(s): 0.0%us, 0.0%sy, 0.0%ni, 88.2%id, 0.0%wa, 0.0%hi, 11.8%si, 0.0%st
Mem: 2028200k total, 184664k used, 1843536k free, 24824k buffers
Swap: 0k total, 0k used, 0k free, 85508k cached


#4

This question may belong on a separate thread, but I’m trying to apt-get install ntop using the debian squeeze and squeeze-backports repositories and am having trouble with python dependencies. Does anyone else have ntop working on helium? and how did you go about it?


#5

So…

Windows file copy reports expected speeds when traversing the two cisco’s across the VyOS bridge. I upped the TCP window size in iPerf and saw expected numbers. Still unsure why the default window size of 64KB bombed when using bridge, but not on same switch, but I don’t care about that now.