Using an index value located on a page table to index page attributes
AssigneeInternation Business Machines Corporation
InventorsTimothy Hume Heil, James Allen Rose, Andrew Henry Wottreng
Life of this patent
Estimating the term…
Abstract
Embodiments of the invention provide methods and apparatus for increasing the number of page attributes specified by a page table while minimizing an increase in size of the page table. According to embodiments of the invention, attribute index bits may be included within a page table and may be used to determine page attributes stored within an attribute index. Additionally, embodiments of the invention provide a plurality of new page attributes.
Claims19
A method of determining page attributes, comprising:
- receiving an instruction which contains a virtual memory address corresponding to page data stored in memory;
- comparing the virtual memory address to a page table;
- based on the comparison of the virtual memory address to the page table, determining at least a page attribute index value for the page data associated with the virtual memory address;
- and
- using the page attribute index value for accessing an attribute index table and determining at least one page attribute of the page data associated with the virtual memory address, wherein the attribute index table comprises of a plurality of page attributes,
- wherein at least one of the plurality of page attributes specifies:
- a first level of cache memory for use when reading data from the page data after a cache miss;
- and
- a second level of cache memory for use when writing data to the page data that is different than the first level of cache memory.
A computer readable storage medium containing a program which, when executed, performs operations comprising:
- receiving an instruction which contains a virtual memory address corresponding to page data stored in memory;
- comparing the virtual memory address to a page table;
- based on the comparison of the virtual memory address to the table, determining at least a page attribute index value for the page data associated with the virtual memory address;
- and
- using the page attribute index value for accessing an attribute index table and determining at least one page attribute of the page data associated with the virtual memory address, wherein the attribute index table comprises of a plurality of page attributes,
- wherein at least one of the plurality of page attributes specifies:
- a first level of cache memory for use when reading data from the page data after a cache miss;
- and
- a second level of cache memory for use when writing data to the page data that is different than the first level of cache memory.
A system, comprising:
- a processing element;
- a page table comprising at least one memory address and a page attribute index value associated with the at least one memory address;
- and
- an attribute index table comprising at least the page attribute index value and at least one page attribute associated with the page attribute index value, wherein the attribute index table comprises of a plurality of page attributes;
- wherein the first processing element is configured to receive an instruction containing the at least one memory address, and compare the at least one memory address to the page table to determine the page attribute index value associated with the at least one memory address, and using the at least one page attribute index value for accessing the attribute index table and determining the page attribute, and
- wherein at least one of the plurality of page attributes specifies:
- a first level of cache memory for use when reading data from the page data after a cache miss;
- and
- a second level of cache memory for use when writing data to the page data that is different than the first level of cache memory.
Dependencies are inferred from the claim text.