This patch adds two new counters to the serverstatus document:

metrics.operation.unsendableCompletedResponses counts the number of operations that completed server-side, but where the produced response could not be sent to the client (i.e. due to a network error with the connection from that client).

metrics.operation.killedDueToClientDisconnect counts the number of operations that were killed before completion because the client that sent the operation disconnected.

Description of Linked Ticket

Similar to SERVER-49201, I am not aware of a strong serverStatus indicator that a socket timeout was encountered in an application. i.e. “operation was interrupted because a client disconnected.” (SERVER-39150)

A count of operations that were halted due to disconnect, or couldn’t return data due to the client closing the socket in 4.0 may be diagnostically useful to determine application behavior.

(fixed typo for SERVER-49201)