How to automatically check for heavy processes at regular intervals

How do I automatically check heavy processes at regular intervals?

I'd like to investigate when the load is on during the night, weekends, and holidays.

I have a vague image like creating a shell and starting it at regular intervals in the scheduler, but
Linux is a beginner and I don't know how to do it.

Please let me know if there is a good way to avoid overloading the server.

The environment is Red Hat Enterprise Linux 6.3.

linux rhel

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