1. A high-performance computing (HPC) system, comprising: at least one processor; a memory communicatively coupled to the at least one processor; a node registrar subsystem, implemented on the at least one processor, that performs logical node management functions and data sharing between HPC subsystems to provide interaction between heterogeneous subsystems, the logical node management functions including at least one of handling state transitions of nodes, adding the nodes, removing the nodes, and updating node properties, wherein the node registrar subsystem comprises a stateless node registrar service and a database for storing node information for nodes in the HPC system, the stateless node registrar service providing high-availability through scale-out of multiple services rather than relying on failover; a management subsystem, implemented on the at least one processor, that performs other management functions other than the logical node management functions, wherein the management subsystem communicates with the node registrar subsystem in performing the other management functions; and a job scheduler subsystem, implemented on the at least one processor, that performs job scheduling functions, wherein the job scheduler subsystem communicates with the node registrar subsystem in performing the job scheduling functions, wherein the management subsystem, the job scheduler subsystem, and the node registrar subsystem are separate, heterogeneous subsystems, and wherein the node registrar subsystem provides communication connections that allow direct communication interaction between the management subsystem, the job scheduler subsystem, and the node registrar subsystem.