Data storage system having packet switching network with latency arbitration

A data storage system having a packet switching network, a cache memory, and a plurality of directors, one portion of such directors being adapted for coupling to a host computer/server and another portion of the directors being adapted for coupling to a bank of disk drives. The plurality of directors and cache memory are interconnected through the packet switching network. Each one of the directors is adapted to transmit different types of information packets to another one of the directors through the network. Each one of the directors is adapted to transmit and receive different types of information packets to another one of the directors or cache memories through the packet switching network. Each one of the cache memories is adapted to receive and transmit different types of information packets to one of the directors through the packet switching network. One type of information packet requires a different degree of latency than another type of information packet. The system includes an arbiter for transmitting the information packets as a function of the latency requirement, a priority assigned to the information packet, and the age of such information packets having been stored in a queue of the transmitting one of the directors, the packet switching network, or one of the cache memories.