Asynchronous invocations work as synchronous

[zakovyrya]

Client blocks on methods that do not return results.
Thrift Wiki http://wiki.apache.org/thrift/ThriftFeatures contains description of expected behavior:

asynchronous invocations - Functions that do not return a result can be invoked asynchronously so the client is not blocked until the server has finished processing the request. The server may execute asynchronous invocations of the same client in parallel/out of order