In reply to a post by AEP:

I don't know the answer to that, but I would very much doubt it. The work that these scripts do is mainly disk-bound so wouldn't affect, or be affected by, cpu-intensive tasks. TBH, provided you have lots of free disk space - and who doesn't nowadays - they shouldn't be necessary. And if you've got a SSD I would even consider the thought of running them less frequently or disabling them altogether; you want to keep changes to SSDs to a minimum.

For those of us without "lots of free disk space" it would be helpful if there was EVIDENCE that these scripts had actually run.
Is there a log or some other way of getting assurance that the 'kron' run has actually taken place?

It's probably time that you learned how to use the "man" command.

Type

man periodic

into a terminal window and you will get full details of the "periodic" command, including how to make it log its results. Mind, if you haven't got loads of free disk space then it's probably time to upgrade your hard disk or just buy an external one. Low disk space is an enemy of performance in any operating system.

Got to the Console app (in the utilities folder).

Look for daily.out, weekly.out and monthly.out.