For the THsHaDisruptorServer, there may not be enough threads to run blocking StorageProxy methods. The current number of worker threads is hardcoded at 2 per selector, so 2 * numAvailableProcessors(), or 64 threads on a 16-core hyperthreaded machine. StorageProxy methods block these threads, so this puts an upper bound on the throughput if hsha is enabled. If operations take 10ms on average, the node can only handle a maximum of 6,400 operations per second. This is a regression from hsha on 1.2.x, where the thread pool was tunable using rpc_min_threads and rpc_max_threads.