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:
Aug. 23, 1994
Filed:
Jan. 21, 1992
Applicant:
Inventor:
William T Fuller, San Jose, CA (US);
Assignee:
Tandem Computers, Incorporated, Cupertino, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
371 101 ; 371 111 ;
Abstract
An apparatus and method for improving the input/output performance of a redundant storage array system. The present invention provides a 'special parity' cache within the controller for a redundant storage array system, and means for determining and caching a quantity known as the 'remaining redundancy row parity' (RRR-parity) block. The RRR-parity block is equal to the old parity block of a redundancy row XOR'd with an old data block being read from the same redundancy row. By caching RRR-parity blocks, Write-intensive storage unit operations can be reduced by up to three input/output accesses.