Hippo CMS 12.6.8 uses too much RAM suddenly what could cause it?

Hi all, i’m running Hippo CMS 12.6.8 for a small project
Sometimes memory usage suddenly spikes close to 8 GB even though

What could cause this?
Could it be indexing or something internal?
Also, is there a way to monitor what’s going on during these spikes?
Maybe some JVM flags I can enable when launching on my VPS server to help diagnose the issue?

Thanks very much