Emc Corporation

Data General Corporation

Michael J McLeod

Jeffrey S Kimmel

Miles Aram De Forest

Robert Anthony Alfieri

Mark A O'Connell

William K McGrath

Guy A Simpson

An operating system for a non-uniform memory access (NUMA) multiprocessor system that utilizes a software abstraction of the NUMA system hardware representing a hierarchical tree structure to maintain the most efficient level of affinity and to maintain balanced processor and memory loads. The hierarchical tree structure includes leaf nodes representing the job processors, a root node representing at least one system resource shared by all the job processors, and a plurality of intermediate level nodes representing resources shared by different combinations of the job processors. The operating system includes a medium term scheduler for monitoring the progress of active thread groups distributed throughout the system and for assisting languishing thread groups, and a plurality of dispatchers each associated with one of the job processors for monitoring the status of the associated job processor and for obtaining thread groups for the associated job processor to execute. The operating system further includes a memory manager for allocating virtual and physical memory using a plurality of memory pools and frame treasuries.

Operating system for a non-uniform memory access multiprocessor system

A method for handling attempts by multiple processing threads to access a shared system resource is disclosed. When a thread attempts to access a locked resource, the thread creates a description of the operation it intended to perform and stores the description on a deferred operation list associated with that resource. The deferred operation list is monitored by the thread which has control of the resource. If one or more entries is detected, the entries are removed from the list and processed by the controlling thread.

Shared resource control using a deferred operations list

Growing community of inventors

Garner, NC, United States of America

Michael J McLeod