Abstract: Disclosed is inhibiting process starvation in a multitasking operating system by providing a first type of scheduling event at periodic timer intervals, providing a second type of second scheduling event in response to a running processes voluntarily relinquishing the processor, and, in response to a scheduling event, replacing an old process with a new process only if the old process has run for more than a predetermined amount of time. The predetermined amount of time may be one half of the timer interval. The system described herein provides a small kernel that can run on a variety of hardware platforms, such as a PowerPC based Symmetrix adapter board used in a Symmetrix data storage device provided by EMC Corporation of Hopkinton, Mass. The core kernel code may be written for the general target platform, such as the PowerPC architecture.

Abstract: The data storage facility includes a plurality of data storage devices coupled through multi-path connections to cache memory. A plurality of interfaces to host processors communicates with the cache memory and with cache tag controllers that define the cache memory again over multiple paths.