Two threads may communicate via shared memory using two different modes. In a polling mode, a receiving thread may poll an indicator set by the sending thread to determine if a message is present. In a blocking mode, the receiving thread may wait until a synchronization object is set by the sending thread which may cause the receiving thread to return to the polling mode. The polling mode may have low latency buy may use processor activity of the receiving thread to repetitively check the indictor. The blocking mode may have a higher latency but may allow the receiving thread to enter a sleep mode or perform other activities.