Using "Trash" takes a long time

I have a site with over 20K posts and when I trash some post, I see that the time it takes is very long. I suspect (but am not sure how to check it) that this is because the trash operation triggers some sort of cache cleaning that takes a long time.
Could there be a feature that would stop or restrict any cache operation triggered when deleting or modifying posts?
(if it's already available, I apologize for asking it here, and would appreciate the pointer)

The issue names no files, tests, or entry points. Start by reproducing the slow Trash operation on a site with more than 20K posts and determine whether cache cleaning is involved. Done would require a clearly scoped way to stop or restrict cache work triggered by deleting or modifying posts, along with verification of the resulting behavior.

Written by the indexing model from the issue text.