The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 22, 1998
Filed:
Mar. 14, 1996
John L Furlani, Raleigh, NC (US);
Sun Micro Systems, Mountain View, CA (US);
Abstract
A novel B tree data structure is taught and implemented for use in conjunction with a tertiary storage system. The tertiary storage system utilizes three levels of memory hierarchy: primary memory, such as RAM; read-write secondary storage, such as disk memory; and lower speed, and less expensive mass storage, for example a CD-ROM. A novel B tree is utilized to access data stored in two or more types of memory, such as a CD-ROM memory and a disk drive memory, and adapts for the provision of updated data stored on the hard disk which either replaces or supplements data stored on the CD-ROM. The B tree includes, for each data bucket, a pointer for both a CD-ROM and a disk drive location, and are, in certain embodiments, used in conjunction with a bit mask to indicate the presence of valid data in a first one of the memories, such as CD-ROM, and, if desired, a bloom filter associated with data stored in the second memory type, such as a magnetic disk, in order to speed accesses. The B tree of this invention is capable of being split, as needed, when entries are inserted into memory.