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How to investigate continuous cpu usage by a process on Windows

My process on a users machine consumes 5-20% cpu continuously even when machine is idle. I cannot repro this issue on my end. So I am bit lost on how can I investigate this issue. Please note that 5-20% cpu consumption that I am talking about is not at machine level; but single process is taking that much cpu when it was taking nothing (~0) earlier. So most likely this is a regression. Here is what I have tried –

  1. Reproducing on my end which was not successful.
  2. Getting process dump from user. But it is snapshot in time and is not giving enough info about cpu usage over time. So cannot conclude what the problem is.

Any idea what data I can use to investigate this issue?