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CPqD / ofsoftswitch13

OpenFlow 1.3 switch.
http://cpqd.github.com/ofsoftswitch13
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Have CPqD switch limitted BW? #220

Closed kuljaree closed 6 years ago

kuljaree commented 8 years ago

Hello all, I used Mininet to generate the simple topology and use RYU controller. I used iperf to generate UDP traffic (100Mbps) between two nodes. I got the UDP throughtput about 51Mbps. I didn't to limit bandwidth by openflow meter.

Can someone give me some suggestions?

mtkh commented 8 years ago

I don't understand what you are looking for? do you want to limit the bandwidth by meters or ?

mtkh commented 8 years ago

if so then use dpctl, here

https://github.com/CPqD/ofsoftswitch13/wiki/Dpctl-Documentation#Meter

kuljaree commented 8 years ago

Thanks mtkh, I'm sorry that my question is not clear. I did experiment and notice that CpqD switch gives UDP throughput about 51 Mbps. This result made me doubt that CpqD switch limit the bandwidth capability or not? In fact the result should be nearly link capacity (100Mbps).

Can you give some suggestions?

mtkh commented 8 years ago

No, I don't think it should limit but try the same with TCP and check please.

kuljaree commented 8 years ago

Hi mtkh, for TCP, I got 43.6 Mbps.

I don't know why I got the poor result. How much you can get?

kuljaree commented 8 years ago

Hi mtkh, I already checked the CPqD switch, it didn't limit by meter as following result. Is CPqD switch limitation or problem?

root@mininet:~# dpctl unix:/tmp/s1 meter-config

SENDING (xid=0xF0FF00F0): stat_req{type="mconf", flags="0x0"{meter_id= ffffffff"}

RECEIVED (xid=0xF0FF00F0): stat_repl{type="mconf", flags="0x0", stats=[]}

ederlf commented 8 years ago

It is a problem in more recent kernels due to TCP offloading. Lots of packets are seeing as larger than the Maximum MTU size and dropped.

Try to disable it using ethtool. Will not be a huge improvement, because the switch is quite slow (~200Mbps) http://www.linuxfoundation.org/collaborate/workgroups/networking/tso

kuljaree commented 8 years ago

Hi ederlf, Thanks for your response. I have disabled tso all interface. It can improve TCP throughput but the result about 51Mbps that is not close 100Mb (BW capacity).

For BW link capacity is 1000Mb, the UDP throughput about 84.3 Mbps and 73.8 Mbps for TCP. (I followed in this link [https://github.com/CPqD/ofsoftswitch13/issues/165] )

Can you give me some suggestions? Thanks