Browse Prior Art Database

Multiple Memory Hypervisor

IP.com Disclosure Number: IPCOM000079960D
Original Publication Date: 1973-Oct-01
Included in the Prior Art Database: 2005-Feb-26
Document File: 2 page(s) / 39K

Publishing Venue

IBM

Related People

Kern, RM: AUTHOR [+2]

Abstract

Some service aid programs simulate the dynamic address translation (DAT) process for translating virtual addresses to real addresses, for both single and multiple virtual memories. This is required, since the service programs execute as problem programs and can have no control over system operation.

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Multiple Memory Hypervisor

Some service aid programs simulate the dynamic address translation (DAT) process for translating virtual addresses to real addresses, for both single and multiple virtual memories. This is required, since the service programs execute as problem programs and can have no control over system operation.

The present technique permits execution of a hypervisor in each memory of a multiple virtual memory system. This allows the hardware system to perform DAT, instead of requiring the hypervisor to simulate the translation process. This results in improved performance. The technique is described as follows: (1) Save the real storage to be occupied by the hypervisor on a private external paging volume (the Hypervisor Paging Volume, or HpV). (2) Provide a mapping in the target memory of the real storage occupied by the hypervisor to an unused portion of virtual storage in the target memory. This is done by modifying the segment and page table entries for the virtual storage to be occupied. (3) Indicate that the virtual storage associated with the saved real storage exists only on the HPV. Thus the saved storage remains at the same virtual storage locations, with the page table entries marked invalid. (4) Commence execution in the target memory.

When references are made to the portion of storage which resides on the HPV, an interruption occurs. The requested page may be brought in by the hypervisor and the page table entry associated with the virt...