I am trying to get some profiling results for an MPI application. I used perf report command on CentOS 7. I searched online and found some wiki for perf, but I still couldn't find the meaning of the first three columns.
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Zack
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According to the perf Tutorial first is the overhead and second one is the self overhead:
The column 'Overhead' indicates the percentage of the overall samples collected in the corresponding function.
The 3rd column in your output is the number of occurrences of the event, called period:
The perf tool defaults to the average rate. It is set to 1000Hz, or 1000 samples/sec. That means that the kernel is dynamically adjusting the sampling period to achieve the target average rate. The adjustment in period is reported in the raw profile data. In contrast, with the other mode, the sampling period is set by the user and does not vary between samples. There is currently no support for sampling period randomization.
Bogdan Kobylynskyi
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