From: Zhang, Yanmin on
More info about the testing:
It's a loopback testing. We start one client netperf process to communicate with netserver process in a stream TCP testing. To reduce the cpu cache effect, we bind the 2 processes on 2 different physical cpus.
#taskset -c 0 ./netserver
#taskset -c 15 ./netperf -t TCP_STREAM -l 60 -H 127.0.0.1 -i 50,3 -I 99,5 -- -s 57344 -S 57344 -m 4096

>>-----Original Message-----
>>From: Shi, Alex
>>Sent: 2010Äê6ÔÂ18ÈÕ 15:17
>>To: eric.dumazet(a)gmail.com; davem(a)davemloft.net
>>Cc: Chen, Tim C; Zhang, Yanmin; linux-kernel(a)vger.kernel.org
>>Subject: TCP stream performance regression due to
>>c377411f2494a931ff7facdbb3a6839b1266bcf6
>>
>>In our netperf testing, TCP_STREAM56 shows about 20% or more performance
>>regression on WSM/NHM and tigerton machines. The testing boot up both
>>netserver and client on localhost. The testing command like this:
>>./snapshot_script_net TC_STREAM56 127.0.0.1
>>
>>We found the following commit causes this issue.
>>c377411f2494a931ff7facdbb3a6839b1266bcf6
>>Revert this commit will recover this regression on all machine.
>>
>>Regards!
>>Alex