However, on some multicomputers with fast interprocessor communication and relatively low memory bandwidth, intraprocessor communication can actually be slower than interprocessor communication. Reading and writing global pointers. Hence, global pointers must be used with caution, particularly on computers where communication is expensive. If a data structure is referenced often, it may be worthwhile to move that data structure to where it is used most often, or to replicate it. If a task requires many data items from the same processor object, it may be better to use an RPC to transfer all the required data in a single message.
Remote procedure calls.
In many situations, the return message is not required and hence represents overhead. This overhead can be avoided by using the spawn statement to create an asynchronous thread of control. Hence, care must be taken if application performance depends on obtaining timely responses to remote requests. However, the cost of these operations can vary significantly from machine to machine. The first processor object creation on a processor is often significantly more expensive than subsequent processor object creation operations on the same processor.