Yes, The Qpid C++ broker has been achieved great benchmark results in published papers by those that redistribute it. Red Hat MRG product build on Qpid has shown 760,000msg/sec ingress on an 8 way box or 6,000,000msg/sec OPRA messages. Latencies have been recored as low as 180-250us (.18ms-.3ms) for TCP round trip and 60-80us for RDMA round trip using the C++ broker.