Other

Cera M Gmbh

E J Weldon, Jr

William D Miller

Gary L Harrington

Lawrence M Fullerton

Christopher M Bellman

Larry M Fullerton

Chris M Bellman

A method for storing data in a memory, including compressing fixed-sized pages of data, and storing the compressed pages into available smaller memory spaces on a medium if the compressed page will fit into such space, or storing the compressed pages onto available larger memory spaces on the medium, if the compressed page will not fit into the smaller space.

Data compression and decompression using memory spaces of more than one

A computer using virtual memory management employs a random-access type storage device such as a semiconductor memory for page swapping. The semiconductor memory is formatted to provide multiple partitions of varying block size, e.g., two block sizes, for compressed pages, and another block size for uncompressed original-sized pages. The data to be stored is in pages of fixed size, and these pages are compressed for storage if the compressed size fits in the block size of one of the small-block partitions in the memory. If a data page is not compressible to one of the small block sizes, it is stored uncompressed in the other full-size partition. The operating system maintains a table storing the locations of the pages in the partitions, so upon recall the page (if compressed) is retrieved from its location found using the table, decompressed and sent to the CPU. The relative number of blocks in the partitioned memory (e.g., the physical storage capacity of the memory) is set (or dynamically allocated) at the average ratio of compressible pages to uncompressible pages for the compression algorithm used. For example, an algorithm may compress 90% of the pages to either 50% or 70% of their original size, so a ratio of the number of locations in the compressed partitions of the semiconductor memory to the number of locations in the uncompressed partition is selected as 90:10. The compression mechanism operates on bytes in bit-parallel format, and uses a lookahead buffer which is compared with bytes in a window to produce 9-bit symbols. The stream of 9-bit symbols passes through an ECC generator, also operating in bit-parallel.

Solid-state RAM data storage for virtual memory computer using

Growing community of inventors

Honolulu, HI, United States of America

E J Weldon, Jr