Abstract: According to the present invention, methods and apparatus are provided for increasing the efficiency of data access in multiple processor, multiple cluster systems. A cache coherence controller associated with a first cluster of processors can determine whether speculative probing can be performed before forwarding a data access request to a second cluster. The cache coherence controller can send the data access request to the second cluster if the data access request can not be completed locally.

Abstract: A computer system is described having a plurality of resources which includes a plurality of processors, a distributed point-to-point transmission infrastructure for interconnecting the plurality of processors, and a partitioning processor for configuring the plurality of resources into at least one partition. Each partition comprises a subset of the plurality of resources. The partitioning processor is operable to configure the resources by enabling at least one link between at least one of the plurality of processors and at least one other one of the plurality of processors according to a previously specified partitioning schema. The link(s) so enabled corresponds to a portion of the point-to-point transmission infrastructure.