Multi-zone relocation facility computer memory system

• US 5,652,853 A
• Filed: 05/31/1995
• Issued: 07/29/1997
• Est. Priority Date: 02/08/1993
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: McCauley, Donald William, Scanlon, John Fenton, Gum, Peter Hermon, Kim, Moon Ju, Krumm, Barry Watson, Duvalsaint, Karl Jean
• Primary Examiner(s): LANE, JOHN A
• Application Number:
  US08/455,818
• Time in Patent Office: 790 Days
• Field of Search: 395/406, 395/425, 395/413
• US Class Current: 711/203
• CPC Class Codes: G06F 12/0284 Multiple user address space allocation, e.g. using different base addresses interprocessor communication G06F15/163

Abstract

A memory reconfiguration system now allows a guest'"'"'s absolute storage space to be mapped to multiple discontiguous host absolute storage space. A multi-zone relocation facility is provided for relocating multiple zones of the memory of the computer system. A control program being executed in its data processing system to reconfigure storages that are assigned to guests when sufficient real addressing capability is not available to provide a range of holes in the host absolute addressing space. Memory can be reconfigured by a control program that allows main storage, and expanded storage associated with a guest'"'"'s real storage to be mapped to multiple discontiguous areas of host absolute spaces. When sufficient real addressing is not available in the host absolute addressing space it allows expansion of the host absolute storage space that maps a guest storage. The system can be used in scalar, parallel and massively parallel computer systems having plural logical processors (LPARs).

Claims

1. In a computer system with a main host memory and a plurality of logical guest processors, each of said logical guest processors assigned a zone in said host memory of contiguous address space defined by a zone origin and a zone limit, a method for dynamically reorganizing said main host memory by means of a control program, said method including the steps of:

activating a multi-zone facility to map for a first logical processor a first guest absolute address zone to at least two discontiguous segments of the main host memory address space, each of said discontiguous segments having a zone origin value and a zone limit value;

removing from a second guest absolute address zone mapped for a second logical processor at least a part of its main host memory address space in one of said at least two discontiguous segments;

blocking access to said part by said second logical processor; and

issuing an instruction to increase the storage limit of said first logical processor after notification by an I/O subsystem response that new zone origin and zone limit values are in effect for said first logical processor.