This reduces the necessary number of threads in the application executor
and provides a small improvement in latency (~15μs, which is normally in
the noise, but would be a 5% improvement).
Benchmark (direct) (transport) Mode Cnt Score Error Units
Before:
TransportBenchmark.unaryCall1024 true INPROCESS avgt 10 1566.168 ± 13.677 ns/op
TransportBenchmark.unaryCall1024 false INPROCESS avgt 10 35769.532 ± 2358.967 ns/op
After:
TransportBenchmark.unaryCall1024 true INPROCESS avgt 10 1813.778 ± 19.995 ns/op
TransportBenchmark.unaryCall1024 false INPROCESS avgt 10 18568.223 ± 1679.306 ns/op
The benchmark results are exactly what we would expect, assuming that
half of the benefit of direct is on server and half on client:
1566 + (35769 - 1566) / 2 = 18668 ns --vs-- 18568 ns
It is expected that direct=true would get worse, because
SerializingExecutor is now used instead of
SerializeReentrantCallsDirectExecutor plus the additional cost of
ThreadlessExecutor.
In the future we could try to detect the ThreadlessExecutor and ellide
Serializ*Executor completely (as is possible for any single-threaded
executor). We could also optimize the queue used in ThreadlessExecutor
to be single-producer, single-consumer. I don't expect to do those
optimizations soon, however.
This reduces the number of classes defined, which reduces memory usage.
It also reduces the number of methods defined, which is important
because of the dex limit.
This should have virtually zero performance degradation because the
contiguous switch uses tableswitch bytecode.
ServerCall already had "headers must be sent before any messages, which
must be sent before closing," but the implementation did not enforce it
and our async server handler didn't obey.
The benefit of forcing sending headers first is that it removes the only
implicit call in our API and interceptors dealing just with metadata
don't need to override sendMessage. The implicit behavior was bug-prone
since it wasn't obvious you were forgetting that headers may not be
sent.
There is no need to use ServerMethodDefinition in codegen. The create()
method itself could be helpful to a dynamic HandlerRegistry
implementation, so we won't remove it.
Client:
* New ManagedChannel abstract class.
* Adding ping to Channel.
* Moving builders and implementations to internal.
Server:
* Added lifecycle management API to Server (mirroring ManagedChannel).
* Moved ServerImpl, AbstractServerBuilder and handler registries to internal.
* New ServerBuilder abstract class (mirroring ManagedChannelBuilder).
Fixes#545
Reserve io.grpc for public API only, and all internal stuff in core to
io.grpc.internal, including the non-stable transport API.
Raise the netty/okhttp/inprocess subpackages one level up to io.grpc,
because they are public API and entry points for most users.
Details:
- Rename io.grpc.transport to io.grpc.internal;
- Move SharedResourceHolder and SerializingExecutor to io.grpc.internal
- Rename io.grpc.transport.{netty|okhttp|inprocess} to
io.grpc.{netty|okhttp|inprocess}
- Remove blockingClientStreamingCall() which is not used, and we don't
actually want that API.
- Rename duplexStreamingCall() to asyncDuplexStreamingCall() to align
with other async methods.
- In unary call and client streaming call, do not request for additional
response after the first response.
This gives us more flexibility in API changes in the future.
Unary call and server streaming call should call the flow-control method
call.request() only once. Previously it was called whenever a request
arrives, which is wrong. Now it's fixed.
Resolves#436
Resolves#511.
- In generated code, make CONFIG private and METHOD_* fields public.
METHOD_* fields are MethodDescriptors now, users of the CONFIG field
should switch to using the METHOD_* fields.
- Move MethodType into MethodDescriptor (#529).
- Unify the fully qualified method name. It is fully qualified service
name + slash + short method name. It doesn't have the leading slash.
- HandlerRegistry switches the key from short method name to fully
qualified method name.