| 摘要 |
In a data processing system, the flow of messages specifying the states of various processes in the system, e.g. the level of an input queue associated with a processor, is regulated using a queue 17 and a current state register 21 which maintains a list of the current states of each process, e.g. "empty" or "filling up" or "full". Whenever a process state message such as a flow control message arrives, the new state of that process is written into the register and an item identifying the process is placed in the queue if a process pending flag memory 25 indicates that an item does not already exist for this process. When an item reaches the front of the queue, the current state of the corresponding process is read from register and used to generate an output flow control message. In this way, the invention regulates flow control messages whilst ensuring the latest control information is communicated. In further embodiments the queue is modified to cope with flow control messages of differing priorities and the processes are grouped into sets to reduce memory requirements. |
