Estimating FLOPS

[Lomesh_A_]

I have Intel(R) Core(TM) i7-4800MQ CPU @ 2.70GHz which is Haswell based processor. I want to estimate FLOPS of an application. I am using Intel VTune Amplifier XE 2015. wondering if anybody knows how to find FLOPS?

I tried following steps on https://software.intel.com/en-us/articles/estimating-flops-using-event-based-sampling-ebs/ but I don't find Processor Event Name on the pages in VTune. wondering if anybody has successfully done this on Haswell processor.

[Peter_W_Intel]

That is so strange, I try this with VTune Amplifier XE 2015 U3 in three boxes:

1. SandyBridge - event FP_COMP_OPS_EXE.SSE_PACKED_DOUBLE for measuring FLOPS,  is available

2. IvyBridge  -  event FP_COMP_OPS_EXE.SSE_PACKED_DOUBLE for measuring FLOPS, is available

3. Haswell  - no associated event is available??

You may change the machine, and submit an issue to https://premier.intel.com.

[Lomesh_A_]

I found http://icl.cs.utk.edu/projects/papi/wiki/PAPITopics:SandyFlops - apparently Haswell doesn't expose floating point counters. wondering if Broadwell is same?

[Peter_W_Intel]

Good article, thank you. I have no Broadwell box on hand to test this:-( 

[Dmitry_P_Intel1]

Hello,

For Broadwell the FLOPs estimation should be based on the following events:

FP_ARITH_INST_RETIRED.SCALAR_SINGLE FP_ARITH_INST_RETIRED.128B_PACKED_SINGLE] * 4 + FP_ARITH_INST_RETIRED.256B_PACKED_SINGLE * 8 + 
FP_ARITH_INST_RETIRED.SCALAR_DOUBLE] + FP_ARITH_INST_RETIRED.128B_PACKED_DOUBLE * 2 + FP_ARITH_INST_RETIRED.256B_PACKED_DOUBLE * 4 + INST_RETIRED.X87

And note that these are retired instructions on Broadwell - not executed as it was for SandyBridge or IvyBridge. 

Thanks & Regards, Dmitry

[Lomesh_A_]

thanks Dmitry. i need to buy Broadwell machine. wondering if you can point me to some documentation meanwhile.

[McCalpinJohn]

The new events for Broadwell have not yet made it into the standard documentation (at least as recently as the April 2015 updates to the Intel Software Developer's Manuals).

The only documentation I have seen for these events is at https://download.01.org/perfmon/BDW/

[Bernard]

Thanks for the link.