[.NET Core, Windows] gRPC server shutdown blocks if child process was spawned

[dubov...@gmail.com]

We are building a cross-platform app that consists of several interdependent processes that interact with each other.

One process starts a gRPC server and then spawns a child process. After having exchanged a few gRPC calls with yet another process it needs to close, but is unable to close the server gracefully - ShutdownAsync task never completes until the child process exits - but we need it to stay up.

Details regarding child processes:

• The child that blocks the shutdown doesn't use gRPC.
• The peers for the interaction are also spawned by the main process, but are closed by the time the main process starts closing.
• Children are spawned using .NET System.Diagnostics.Process API. If the latter is replaced with CreateProcess P/Invoke with inheritHandles=false, the problem disappears, but that would be a work-around, not the solution, assuming we are aiming for cross-platform code.

 

Could this be the same issue as the "fork() not supported" issue in Python version?

Does it mean that out scenario is not supported too?