Errors when running doing ib testing with ib_write_lat

I was doing a ib test using  perftest package which has simple tests for benchmarking IB bandwidth and latency. the 2 simple packages are ib_write_bw and ib_write_lat. 

On the Server side, I launched

# ib_write_lat -a

------------------------------------------------------------------
                    RDMA_Write Latency Test
 Number of qps   : 1
 Connection type : RC
 Mtu             : 2048B
 Link type       : IB
 Max inline data : 400B
 rdma_cm QPs     : OFF
 Data ex. method : Ethernet
------------------------------------------------------------------
 local address: LID 0x03 QPN 0x0065 PSN 0xba11f4 RKey 0x003900 VAddr 0x002ab9bad9600

On the Client Side,

# ib_write_lat -a 192.168.5.1

The errors are as followed

Conflicting CPU frequency values detected: 1200.000000 != 2501.000000
 2       1000          inf            inf          inf
Conflicting CPU frequency values detected: 1200.000000 != 2501.000000
 4       1000          inf            inf          inf
Conflicting CPU frequency values detected: 1200.000000 != 2501.000000
 8       1000          inf            inf          inf
Conflicting CPU frequency values detected: 1200.000000 != 2501.000000
 16      1000          inf            inf          inf
Conflicting CPU frequency values detected: 1200.000000 != 2501.000000
 32      1000          inf            inf          inf

To solve the issues, use "-F" option while running the tests. The flag will ignore "Conflicting CPU frequency" errors. Although there will still be error messages, but with "-F", you will also see the results at least

A better solution is to disable the cpuspeed if you are on CentOS. For more information see blog entry