1. A network file server comprising: a data processor; a disk storage array storing data; network adapters for linking the data processor to a data network for exchange of data packets between the data processor and clients in the data network; and storage adapters linking the data processor to the disk storage array for exchange of data blocks between the data processor and the disk storage array; wherein the data processor includes at least eight core central processing units (CPUs), and shared memory shared among the core CPUs and containing programs executable by the core CPUs; wherein the programs executable by the core CPUs include a real-time scheduler for scheduling execution of real-time and general purpose threads, and a thread manager for managing execution of hard affinity threads and soft affinity threads of the general purpose threads, each of the hard affinity threads being executed exclusively by a respective one of the core CPUs, and the thread manager distributing execution of the soft affinity threads among the core CPUs for load balancing; wherein the programs executable by the core CPUs further include: a network adapter interrupt routine for responding to interrupts from the network adapters when the network adapters receive data packets from the data network; a network stack for transmission of data through the network adapters between the data processor and the data network in accordance with a network data transmission protocol; a file system stack for providing clients in the data network with access to the data storage array in accordance with a file system access protocol and for maintaining an in-core file system cache in the shared memory; a storage access driver for accessing the data storage array in accordance with a storage access protocol; and a disk adapter interrupt routine for responding to interrupts from the disk adapters when the disk adapters receive data blocks from the disk storage array; wherein threads of the network stack are incorporated into the real time threads that are scheduled by the real-time scheduler and executed exclusively by a plurality of the core CPUs that are not interrupted by the disk adapter interrupts so that the disk adapter interrupts do not interrupt execution of the network stack; and wherein instances of the storage access driver are hard affinity threads; and wherein the soft affinity threads include a multitude of instances of a thread of the file system stack for file access request processing so that file access request processing for a multitude of concurrent file access requests is load balanced over the core CPUs.