Issue

• Have dual boot the system with RHEL 7.2 kernel-3.10.0-327.4.5.el7.x86_64 and RHEL 6.6 kernel-2.6.32-504.8.1.el6.x86_64. Then have used the sockperf tool after booting in each OS to test the latency.
• As per analysis it is found that latency is seen high if system is booted with RHEL 7.2.
• Below are the results of sockperf after booting in each of the OS

RHEL 7.2

sockperf: ESC[2;35m == version #2.5. == ESC[0m
sockperf[CLIENT] send on:sockperf: using recvfrom() to block on socket(s)

[ 0] IP = 10.10.1.19      PORT = 11111 # TCP
sockperf: Warmup stage (sending a few dummy messages)...
sockperf: Starting test...
sockperf: Test end (interrupted by timer)
sockperf: Test end (interrupted by signal 2)
sockperf: Test ended
sockperf: [Total Run] RunTime=10.100 sec; SentMessages=606030; ReceivedMessages=6060
sockperf: ========= Printing statistics for Server No: 0
sockperf: [Valid Duration] RunTime=9.995 sec; SentMessages=599701; ReceivedMessages=5998
sockperf: ESC[2;35m====> avg-lat= 12.252 (std-dev=0.171)ESC[0m
sockperf: # dropped messages = 0; # duplicated messages = 0; # out-of-order messages = 0
sockperf: Summary: Latency is 12.252 usec <---

RHEL 6.6

sockperf: ESC[2;35m == version #2.5. == ESC[0m
sockperf[CLIENT] send on:sockperf: using recvfrom() to block on socket(s)

[ 0] IP = 20.20.1.19      PORT = 11111 # TCP
sockperf: Warmup stage (sending a few dummy messages)...
sockperf: Starting test...
sockperf: Test end (interrupted by timer)
sockperf: Test end (interrupted by signal 2)
sockperf: Test ended
sockperf: [Total Run] RunTime=10.100 sec; SentMessages=606030; ReceivedMessages=6060
sockperf: ========= Printing statistics for Server No: 0
sockperf: [Valid Duration] RunTime=9.994 sec; SentMessages=599701; ReceivedMessages=5998
sockperf: ESC[2;35m====> avg-lat=  8.853 (std-dev=0.315)ESC[0m
sockperf: # dropped messages = 0; # duplicated messages = 0; # out-of-order messages = 0
sockperf: Summary: Latency is 8.853 usec