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:
Feb. 04, 1997
Filed:
Jan. 11, 1995
James F Macon, Jr, Boynton Beach, FL (US);
Shauchi Ong, San Jose, CA (US);
Feng-Hsien W Shih, Hsien-Chu, TW;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A file-based Read-ahead method employs asynchronous I/O processes to fetch Demand and Read-ahead data blocks from a disk (4), depending on their physical and logical sequentialities. When a file system (10) issues an I/O address to obtain data blocks from a file, it also determines the disk location of data blocks that are logically consecutive with the demanded data. The number of such data blocks to be determined in this process is accomplished in accordance with a dynamic Read-ahead method. If the data blocks are physically consecutive, a single I/O request is sent to a disk driver to obtain both the Demand data block and to Prefetch the Read-Ahead data block(s). If, instead, the data blocks are found not to be physically consecutive, a plurality of asynchronous disk I/O requests are issued so as to separately obtain the Demand and the Read-Ahead data blocks.