Most serverStatus metrics have names in camelCase. There are at least these exceptions, all defined in src/mongo/db/stats/counters.cpp:

query.planCache.sbe.replanned_plan_is_cached_plan
query.planCache.sbe.cached_plans_evicted
query.planCache.sbe.inactive_cached_plans_replaced
query.planCache.classic.replanned_plan_is_cached_plan
query.planCache.classic.cached_plans_evicted
query.planCache.classic.inactive_cached_plans_replaced

This caused some issues when registering metrics for OTel, because it performs some validation for serverStatus metric names, expecting camelCase.

All of these metrics were released in 8.2.

If we were to change these names to be consistent with the other metrics, we should be sure not to break anything downstream. I did some digging:

• Ask the Internal Data Platform Team #ask-data, specifically ping @server_analytics, as they may be using this field. Renaming it would cause it to appear as a completely separate field in the DWH.
• Ask Intel #ask-cloud-intel, as they will need to make updates on their end.
• Update documentation for serverStatus

Ultimately it may not be worth it, but I wanted to document why here.