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Title: Method and apparatus for two-layer copy-on-write

Abstract

A system, apparatus and method are provided in which a range of virtual memory addresses and a copy of that range are mapped to the same first system address range in a data processing system until an address in the virtual memory address range, or its copy, is written to. The common system address range includes a number of divisions. Responsive to a write request to an address in a division of the common address range, a second system address range is generated. The second system address range is mapped to the same physical addresses as the first system address range, except that the division containing the address to be written to and its corresponding division in the second system address range are mapped to different physical addresses. First layer mapping data may be stored in a range table buffer and updated when the second system address range is generated.

Inventors:
; ;
Issue Date:
Research Org.:
Arm Ltd., Cambridge (United Kingdom)
Sponsoring Org.:
USDOE
OSTI Identifier:
1632575
Patent Number(s):
10565126
Application Number:
15/649,930
Assignee:
Arm Limited (Cambridge, GB)
Patent Classifications (CPCs):
G - PHYSICS G06 - COMPUTING G06F - ELECTRIC DIGITAL DATA PROCESSING
Resource Type:
Patent
Resource Relation:
Patent File Date: 07/14/2017
Country of Publication:
United States
Language:
English

Citation Formats

Beard, Jonathan Curtis, Rusitoru, Roxana, and Dunham, Curtis Glenn. Method and apparatus for two-layer copy-on-write. United States: N. p., 2020. Web.
Beard, Jonathan Curtis, Rusitoru, Roxana, & Dunham, Curtis Glenn. Method and apparatus for two-layer copy-on-write. United States.
Beard, Jonathan Curtis, Rusitoru, Roxana, and Dunham, Curtis Glenn. Tue . "Method and apparatus for two-layer copy-on-write". United States. https://www.osti.gov/servlets/purl/1632575.
@article{osti_1632575,
title = {Method and apparatus for two-layer copy-on-write},
author = {Beard, Jonathan Curtis and Rusitoru, Roxana and Dunham, Curtis Glenn},
abstractNote = {A system, apparatus and method are provided in which a range of virtual memory addresses and a copy of that range are mapped to the same first system address range in a data processing system until an address in the virtual memory address range, or its copy, is written to. The common system address range includes a number of divisions. Responsive to a write request to an address in a division of the common address range, a second system address range is generated. The second system address range is mapped to the same physical addresses as the first system address range, except that the division containing the address to be written to and its corresponding division in the second system address range are mapped to different physical addresses. First layer mapping data may be stored in a range table buffer and updated when the second system address range is generated.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2020},
month = {2}
}

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