Tracking issue for ServerCallExecutorSupplier API being experimental

[YifeiZhuang]

Allows for defining an executor per-service or per-method. Discussed in #7874.
This does not replace ServerBuilder.execute(), which is a the default executor to run tasks before the point when executorSupplier can be called, or as a fallback executor when executorSupplier returns nothing.

If ServerBuilder.executorSupplier() is provided, ServerBuilder.directExecutor() is automatically disabled.

[ejona86]

If ServerBuilder.executorSupplier() is provided, ServerBuilder.directExecutor() is automatically disabled.

@YifeiZhuang, is this true? I think directExecutor still functions as would be expected from the user's perspective, we just disable a directExecutor optimization.

[YifeiZhuang]

If ServerBuilder.executorSupplier() is provided, ServerBuilder.directExecutor() is automatically disabled.

@YifeiZhuang, is this true? I think directExecutor still functions as would be expected from the user's perspective, we just disable a directExecutor optimization.

yup I was wrong. If ServerBuilder.executorSupplier() is provided, ServerBuilder.directExecutor() is still effective, just stream optimization and synchronization optimization are disabled, and only the handleServerCall() will be handled on the supplied executor instead of the running on direct executor.