What does the percent of CPU time mean in total time?

Chia Plotting
1
  • Total time = 17182.295 seconds. CPU (135.140%) Wed Apr 14 08:45:14 2021

Would you please tell me what is the meaning of CPU (135.140%)? Thank you!

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I would assume this means total CPU utilization for the plot, strongly related to the number of threads chosen for the plot, and remember only phase 1 of plotting is multi-threaded ā€“ but Iā€™m not entirely sure what it means specifically.

Maybe someone with more knowledge than me can answer.

4

My guess is just user time / wall time to get 135%.
codinghorror is right about the threading. So it will be more informative if you can dig up how long does it take to complete phase 1 (wall time), and find user time in ps and compare the two (plotman did it for you). Say if you fire up 8 threads (-r 8), but the ratio is only 2, then probably this task is contending with others and this will cause cpu to context switch a lot.

Put it in another way if you know how hyper threading works and if you are trying to use up all cores, then the ratio is not going to be > 2. I think for phase 1, the ratio 1.5-1.8 is ok.

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