(54) METHOD OF RESOURCE ARBITRATION
(75) Inventors: Jeffrey Douglas Brown, Rochester, MN (US); Scott Douglas Clark, Rochester, MN (US); Charles Ray Johns, Austin, TX (US); Takeshi Yamazaki, Austin, TX (US)
(73) Assignee: International Business Machines Corporation, Armonk, NY (US)
( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 202 days.
(21) Appl. No.: 10/730,952
(22) Filed: Dec. 9, 2003
(65) Prior Publication Data
US 2005/0125581 Al Jun. 9, 2005
U.S. CI 710/240; 710/243; 710/244
Field of Classification Search 710/240 244,
710/116, 119, 120; 370/230.1, 412, 395.41, 370/395.42, 395.43 See application file for complete search history.
U.S. PATENT DOCUMENTS 5,832,278 A * 11/1998 Pham 710/243
An improved method and apparatus for resource arbitration. Four priority classes, managed high (MH), managed low (ML), opportunistic high (OH) and opportunistic low (OL), are defined. A priority class is assigned to each resource access request. An access request concentrator (ARC) is created for each resource, through which the resource is accessed. An access request is chosen at each ARC using the priority order MH, ML, OH, and OL, in decreasing order of priority. If OH priority class resource access requests are locked out, the priority order is temporarily changed to OH, OL, MH, and ML, in decreasing order of priority. If OL priority class resource access requests are locked out, the priority order is temporarily changed to MH, OL, OH, and ML, in decreasing order of priority.
18 Claims, 4 Drawing Sheets