1. A method to synchronize contexts between as producer engine and a consumer engine, the method comprising: executing a context at a producer engine, the executing including updating as memory register; and sending a signal from the producer engine to a consumer engine that the memory register has been updated, the signal including a Context ID to identify a context to be executed by the consumer engine to update the register; determining at the consumer engine whether the Context ID of the signal matches a Context ID of a context currently being processed at the consumer engine; and waiting at the consumer engine if the Context ID of the signal message matches the context currently being processed by the consumer engine.