High cpu every 15 minutes and hight ops every 5 minutes

Dear Community
I have noticed repeated spikes in the performance monitor of my Atlas M20 5.0.18 on GCP

  1. Every 15 minutes there is a CPU spike
  2. Every 5 minutes there is a spike for delete ops

The regularity is noteworthy.
I have no such scheduled logical operation on my database (and no deletes at all).

Any idea where these com from?

This looks like you might have a TTL index that does automatic delete on expired documents.