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:
Jul. 04, 2000
Filed:
Oct. 24, 1997
Madhumitra Sharma, Shrewsbury, MA (US);
Chester Pawlowski, Westford, MA (US);
Kourosh Gharachorloo, Stanford, CA (US);
Stephen R Van Doren, Northborough, MA (US);
Simon C Steely, Jr, Hudson, NH (US);
Compaq Computer Corp., Houston, TX (US);
Abstract
An improved I/O processor (IOP) delivers high I/O performance while maintaining inter-reference ordering among memory reference operations issued by an I/O device as specified by a consistency model in a shared memory multiprocessor system. The IOP comprises a retire controller which imposes inter-reference ordering among the operations based on receipt of a commit signal for each operation, wherein the commit signal for a memory reference operation indicates the apparent completion of the operation rather than actual completion of the operation. In addition, the IOP comprises a prefetch controller coupled to an I/O cache for prefetching data into cache without any ordering constraints (or out-of-order). The ordered retirement functions of the IOP are separated from its prefetching operations, which enables the latter operations to be performed in an arbitrary manner so as to improve the overall performance of the system.