The present invention relates generally to multi-processor computer systems. More specifically, the present invention provides techniques for building computer systems having a plurality of multi-processor clusters.
A relatively new approach to the design of multi-processor systems replaces broadcast communication among processors with a point-to-point data transfer mechanism in which the processors communicate similarly to network nodes in a tightly-coupled computing system. That is, the processors are interconnected via a plurality of communication links and requests are transferred among the processors over the links according to routing tables associated with each processor. The intent is to increase the amount of information transmitted within a multi-processor platform per unit time.
One limitation associated with such an architecture is that the node ID address space associated with the point-to-point infrastructure is fixed, therefore allowing only a limited number of nodes to be interconnected. The infrastructure is also flat, therefore allowing only a single level of mapping for address spaces and routing functions. In addition, the processing throughput for transactions in a computer system employing such a point-to-point data transfer mechanism may be limited by the capacity of the protocol engine responsible for processing those transactions.
It is therefore desirable to provide techniques by which computer systems employing such an infrastructure as a basic building block are not so limited.