C++ gRPC thread number configuration

It depends whether you are using sync or async API. For a sync client, your RPC calls blocks the calling thread, so it is not really relevant. For a sync server, there is an internal threadpool handling all the incoming requests, you can use a grpc::ResourceQuota on a ServerBuilder to limit the max number of threads used by the threadpool. For async client and server, gRPC uses CompletionQueue as

[nikezono]

gRPCでスレッドプールのスレッド数上限を定数として与えたい