SERVER-49107 and SERVER-51690 changed the command execution path for mongod and mongos, respectively, to use future continuations and allow asynchronous execution of database commands. These future continuations add some overhead to command execution and could reduce the average throughput by up to 8%.

This ticket should investigate possible improvements that reduce the cost of the future continuations. In particular, reducing the number of future continuations (i.e., the number of then and onError continuations), using fewer allocations in service_entry_point_common.cpp and strategy.cpp, and improving the infrastructure to construct recursive futures (see here) could help with reducing the execution overhead.

Acceptance criteria: writing new tickets that will improve the performance of command execution path, for both mongod and mongos.