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:
Nov. 22, 1994
Filed:
Nov. 19, 1992
Roger E Hough, Highland, NY (US);
Kazuo Iimura, Yamato, JP;
Kenya Ishimoto, Machida, JP;
Masao Nishimoto, Tokyo, JP;
Akio Saitoh, Tokyo, JP;
Kozo Sawada, Ichikawa, JP;
Fumiaki Abe, Ichikawa, JP;
Goroh Sasaki, Yokohama, JP;
Stephen J Schmandt, Tokyo, JP;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A technique, specifically apparatus and an accompanying method, for use in, e.g., a 'host' operating system (610), for properly updating a dynamically alterable channel program that controls an input/output (I/O) device so as to emulate a 'guest' computer system, that employs dynamic address translation (DAT) in an I/O channel sub-system (150), on a 'host' computer system (10) that does not. This technique performs this updating in a manner that significantly increases channel throughput so as to substantially reduce a performance degradation that would otherwise result from a lack of channel DAT on the host system. Specifically, our technique relies on program controlled interrupt (PCI) chaining coupled with use of 'just-in-time' translation of each new virtual channel program segment generated by a guest operating system (620) and corresponding updating of channel program (415) then executing on the host computer system.