The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 23, 1999
Filed:
Jun. 07, 1995
William H Schwartz, Delray Beach, FL (US);
Suresh Yanamadala, Deerfield Beach, FL (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and system for allowing multiple tasks to share virtual memory areas, in a memory management system for a computer, uses an independent address space created such that it can be 'attached' to multiple address spaces. Any change to the shared address space is reflected in all attached address spaces with just one operation to the shared address space. Entities in the shared address space require only one set of system resources. Since the same powerPC virtual segment ID is used for all attached address spaces, only one set of powerPC page table entries is needed. A feature is attaching shared memory with and without control privileges to provide protection; tasks with privilege can manipulate the address space using the same operations and base addresses as in the non-shared normal address space, and tasks with normal attachment can only reference the memory objects in the overlaid shared address space--memory objects can not be created or destroyed.