Vtune lost part of cpu data

I've run spec2006 benchmarks with Vtune. Somtimes, Vtune lost part of cpu event data but bandwidth data was ok.

I ran app by command line like this:/opt/intel/vtune_amplifier_xe_2016.3.0.463186/bin64/amplxe-cl  -c memory-access -knob analyze-mem-objects=true -knob mem-object-size-min-thres=1024 -knob sampling-interval=1 -data-limit=0 /cpu2006/benchspec/CPU2006/471.omnetpp/run/run_base_ref_amd64-m64-gcc42-nn.0000/omnetpp_base.amd64-m64-gcc42-nn omnetpp.ini 

The result was:

 the CPU time is too small and there was no cpu idle or spin etc.

There is no core data after ~200sec but bandwidth data and uncore events. I think that Vtune lost data because everything was ok when I retested same benchmark. 

I want to know why that problem occur and how to prevent that. 

Thanks!