Michael Z Burrows

US Patent:

6377530, Apr 23, 2002

Filed:

Feb 12, 1999

Appl. No.:

09/249182

Inventors:

Michael Burrows - Palo Alto CA

Assignee:

Compaq Computer Corporation - Houston TX

International Classification:

G11B 390

US Classification:

369 5921, 369 471, 369 303, 704500, 84609

Abstract:

A portable audio player stores a large amount of compressed audio data on an internal disk drive, and loads a portion of this into an internal random access memory (RAM) which requires less power and less time to access. The audio player plays the data stored in RAM and monitors the amount of unplayed data. When the amount of unplayed data falls below a threshold, additional data is copied from the disk drive into RAM. When the portable audio player is turned off, a predetermined amount of audio data is stored in a fast-access non-volatile flash memory unit. When the audio player is turned back on, and play is resumed, a suitable portion of this data can be played while data is being loaded from the disk drive into RAM, thus reducing the amount of time a user must wait before receiving data in response to a play request.

US Patent:

6378087, Apr 23, 2002

Filed:

Jun 8, 1999

Appl. No.:

09/327999

Inventors:

Cormac A. Flanagan - Sunnyvale CA
Michael Burrows - Palo Alto CA

Assignee:

Compaq Computer Corporation - Houston TX

International Classification:

G06F 9455

US Classification:

714 38, 714 4

Abstract:

The disclosed program checker checks whether a program internally tests for error codes that may be returned by procedures used by the program. The program being tested is executed. Each time that a subroutine in the program is about to perform a subroutine or procedure return operation, a program interpreter is invoked. The program interpreter simulates continued execution of the program once for a good return value and once for each error condition return value that is listed in an error condition table entry for the subroutine in which the return operation is being performed. For each simulation of the program, the program interpreter determines the execution path of the program and then compares the execution path for each error condition return value with the execution path for the good return value. If the execution path for any error condition return value is the same as the execution path for a good return value, an error report is generated to indicate that the corresponding error condition return value is not checked by the program.

US Patent:

6438740, Aug 20, 2002

Filed:

Aug 21, 1997

Appl. No.:

08/915701

Inventors:

Andrei Zary Broder - Menlo Park CA
Michael Burrows - Palo Alto CA
Monika Hildegard Henzinger - Menlo Park CA

Assignee:

Compaq Information Technologies Group, L.P. - Houston TX

International Classification:

G06F 945

US Classification:

717 8, 717 9, 712228

Abstract:

A system and method for identifying free registers within a program. A depth first search of a flow diagram representing the execution of a program is performed. The search proceeds simultaneously for all the registers and identifies the free registers from the search. The free registers may then be utilized for various applications without saving and restoring the contents of these registers to memory. The system may limit the amount of time spent searching for free registers with a timer.

US Patent:

6598051, Jul 22, 2003

Filed:

Sep 19, 2000

Appl. No.:

09/664647

Inventors:

Janet L. Wiener - Palo Alto CA
Raymond P. Stata - Palo Alto CA
Michael Burrows - Palo Alto CA

Assignee:

Altavista Company - Palo Alto CA

International Classification:

G06F 1700

US Classification:

707100, 707 10, 707 2, 707102, 7071041, 709201, 709218, 709224

Abstract:

A connectivity server for a collecting, arranging and representing data defining the interconnection of pages on the World Wide Web (Web). A URL Database stores URLs and associates a fingerprint and CS_id with each URL. The URL Database interface is operable to translate between any two of a URL, a fingerprint, and a Host_id. A Host Database associates a Host_id with each distinct hostname in the URL Database. The Host Database interface is operable to accept a Host_id and return a number equal to the number of URLs on the respective host and to return the CS_ids of those URLs. A Link Database stores links between source URLs and destination URLs. The Link Database interface is operable to retrieve, for a given CS_id, the number of inlinks to and outlinks from the URL corresponding to the CS_id. In an embodiment characterized by a single processor, with access to all databases stored in RAM links and URL information may be retrieved sufficiently rapidly so that applications that touch every link, even multiple times, may execute in real time, in a few minutes or hours. Representative applications enabled by the connectivity server include static ranking of pages (eigenranks), query precomputation, mirror-site detection, and related-page identification.

US Patent:

6662364, Dec 9, 2003

Filed:

Nov 5, 1999

Appl. No.:

09/434831

Inventors:

Michael Burrows - Palo Alto CA
Mark Thierry Vandervoorde - Sunnyvale CA
Sanjay Ghemawat - Mountain View CA

Assignee:

Hewlett-Packard Company, L.P. - Houston TX

International Classification:

G06F 900

US Classification:

718102, 718100, 718104

Abstract:

A system and method for implementing mutual exclusion locks (mutexes) is provided. Mutexes of the present invention designate whether they are to be synchronized using fast nonatomic load/store sequences or, alternatively, expensive atomic hardware instructions. When a requesting thread requests a target mutex, the target mutex is synchronized using the method designated by the target mutex. In some embodiments, the designated synchronization method may be changed to the atomic method when the requesting thread is not the thread associated with the target mutex. In other embodiments, the designated synchronization method may be determined by a heuristic function. For example, the synchronization method may be changed to the atomic method when a mutex request counter, which penalizes thread changes, underflows. Other possible heuristic functions may consider factors such as whether the recursion overflow bit of the target mutex has been set, the percentage of mutexes, created by a predetermined call state, that have been converted to the atomic method, and/or the overall percentage of mutexes in the system that have been converted to the atomic method.

US Patent:

6701317, Mar 2, 2004

Filed:

Sep 19, 2000

Appl. No.:

09/664617

Inventors:

Janet Lynn Wiener - Palo Alto CA
Michael Burrows - Palo Alto CA

Assignee:

Overture Services, Inc. - Pasadena CA

International Classification:

G06F 1730

US Classification:

707 10, 7071041, 709201, 709218, 709224

Abstract:

A process for constructing a server for collecting, arranging and storing data that defines the connectivity of pages on the World Wide Web (Web). The process input is a set of compressed ASCII links files, wherein each links file is a series of source URLs and corresponding destination URLs. A temporary URLs_info Table is created and initialized. The links files and URLs metadata are read. Buffers of unique URLs are sorted and written from the links files into URL runs. An ID Index is created from the URL_info table. CS_ids are assigned to URLs and written to the ID Index. Both a compressed URL data structure and a URL Index are created. A Host Table is created. URL fingerprints are converted to CS_ids, and preliminary outstarts to CS_ids and preliminary outstarts and outlinks tables are created. Compressed outstarts and outlinks tables are created from the preliminary tables. Subsequently, compressed instarts and inlinks tables are created based on the outstarts and outlinks tables.

US Patent:

6745194, Jun 1, 2004

Filed:

Aug 3, 2001

Appl. No.:

09/920851

Inventors:

Michael Burrows - Palo Alto CA

Assignee:

Alta Vista Company - Palo Alto CA

International Classification:

G06F 1730

US Classification:

707101, 707102

Abstract:

A technique for deleting duplicate records referenced in an index of a database is disclosed. In one embodiment, the technique may be realized by receiving a record; determining a fingerprint for the record; comparing the fingerprint of the record with fingerprints of previously indexed records; and, when the comparing act determines that the fingerprint of the current received record is the same as at least one of the fingerprints of any of the previously indexed records, identifying the current record as a record to be deleted.

US Patent:

6961930, Nov 1, 2005

Filed:

Mar 31, 2000

Appl. No.:

09/540952

Inventors:

Carl A. Waldspurger - Atherton CA, US
Michael Burrows - Palo Alto CA, US

Assignee:

Hewlett-Packard Development Company, L.P. - Houston TX

International Classification:

G06F009/45

US Classification:

717141, 717139, 717131

Abstract:

The performance of an executing computer program on a computer system is monitored using latency sampling. The program has object code instructions and is executing on the computer system. At intervals, the execution of the computer program is interrupted including delivering a first interrupt. In response to at least a subset of the first interrupts, a latency associated with a particular object code instruction is identified, and the latency is stored in a first database. The particular object code instruction is executed by the computer such that the program remains unmodified.