Multi-node system and method for partitioning a node of the multi-node system into more than one partition

Partitioning a node of a multi-node system into more than one partition is disclosed. First resources of the node are physically partitioned into more than one partition. The first resources physically partitioned to each partition are directly inaccessible by other partitions of the node. Second resources of the node are then internally logically partitioned into the more than one partition. Each second resource internally separates transactions of one partition from transactions of other partitions. Furthermore, the node can be dynamically repartitioned into other partitions, such as a single partition, without having to take the multi-node system down. Operating system (OS) instances of the partitions may have assumptions provided to allow for dynamic partitioning, such as quiescing the processors and/or the input/output components being reconfigured, purging remote cache entries across the entire OS, etc. Each partition may have associated therewith registers that are protected from access by other partitions.