Metadata usage and warnings

I have 960 Gb alloted for my bucket and there is 431 GB of metadata usage and 694 GB user data in memory.
mem_used is 750 Gb
Low watermark is 720 Gb
High watermark is 816 Gb

I am getting Metadata overhead warning that say Over 50% of RAM allocated to bucket “my_bucket” on nodes is taken up by keys and metadata, where as I’m using less than 50% of total ram allocated to my bucket for metadata.

Or is metadata threshold defined on the high watermark?

Could anyone help me understand what I’m missing here.

Also these metadata warnings are sometimes logged to the couchbase panel log and most of the times they are not. Why do we see an inconsistency in the logging.