When grpc client buffers in HTTP/2

[hitti...@gmail.com]

Recently, I asked a question when the deadline starts to count down. (grpc Issue #19155) One told me that the time taken for buffering in HTTP/2, TCP and the network is all part of deadline count down. But when gprc client buffers in HTTP/2. Does the client buffer the requests when the user calls `stub->Echo(&context, request, response)`? I hope anyone acquainted with that can help me. Thanks! 

[Carl Mastrangelo]

Hi, 

The deadline starts as soon as it gets from the Stub into the core library (i.e. after it passes through all interceptors).   The "deadline" is a specific point in time after which the RPC is no longer valid.   When you set a deadline on an RPC, the buffering doesn't come into account, since buffering or no buffer, the point in time has not changed.   Compare this to the similar "timeout" which is a relative amount of time and does get affected by buffering.   gRPC exposes the former to make reasoning about when the RPC.