We're currently running:

• Mongoid 7.0.13
• Mongo ruby driver 2.17
• Atlas replica set 5.0.25 (M80) 

I upgraded the version of the mongo-ruby-driver to 2.19.3, with the only changes being updating a few places that used bulkWrite to ensure not to call if we were passing an empty array.

Our P90 response time is around 800ms and when I deployed this change, they consistently went up to over 1800ms, and when this change was reverted, they dropped back to expected levels.

Many thanks