Hello @Fin_Perlak wellcome to the community!
Thank you for your input. These are valid points, I thing I should have worded it different.
How can I determine the size of active documents in the WiredTiger cache?
The WiredTiger cache will fill up over time but not all documents in the cache are “active” some might be old and just remain in cache. The critical part is when the WiredTiger cache is filled by the indexes and only active documents since then the system needs to start paging and this will be slow. I want to know before when it get’s critical.
If you or any reader has an idea how to get this number I’d be happy if you could share your knowledge with us.
Regards,
Michael