Scheduler for a software system having means for allocating tasks

• US 6,263,358 B1
• Filed: 08/25/1998
• Issued: 07/17/2001
• Est. Priority Date: 07/25/1997
• Status: Expired due to Term

• Current Assignee: British Telecommunications PLC (BT Group PLC)
• Original Assignee: British Telecommunications PLC (BT Group PLC)
• Inventors: Lee, Lyndon C, Ndumu, Divine T, Nwana, Hyacinth S
• Primary Examiner(s): BANANKHAH, MAJID A
• Application Number:
  US09/125,758
• Time in Patent Office: 1,057 Days
• Field of Search: 709/100, 709/102, 709/103, 709/104, 709/105, 709/108, 709/101, 709/106, 709/107
• US Class Current: 718/100
• CPC Class Codes: G06F 8/458 Synchronisation, e.g. post-wait, barriers, locks synchronisation among tasks G06F9/52
• CPC Class Codes: G06F 9/4881 Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues

Abstract

A community of collaborative software agents works together in a domain to provide functionality such as provision of communications services or control of a chemical process. A scheduler is built into each collaborative agent which schedules tasks allocated to that particular agent and tasks sub-allocated by that agent. The scheduler has a mechanism for over-booking tasks for any one agent. It can also make tentative bookings which can be overwritten or timed out.

Claims

1. A module for use in a software system for distributed control, monitoring or management of a process or apparatus, the module comprising:

(i) a communication means for communicating with other such software modules;

(ii) executable software for use in coordinating with the other such software modules in a selection of tasks to be allocated among software modules;

(iii) a data store, or access to a data store, for storing task definition data including ti me data indicating task execution times, and

(iv) a scheduling means for storing data selected from at least one of said task definitions, including said time data for the respective task definition or definitions, wherein said module is adapted to interact with one or more of the other such software modules in accordance with the executable software to store the data selected from said one or more task definitions, wherein the scheduling means is adapted to store task definition data from two or more tasks such that when the software system comprises two or more of said such modules, at least part of two or more tasks may be performed concurrently by each of the said modules.

2. A module according to claim 1 wherein the scheduling means for one module may arrange task definition data so as to determine the order in which, in use of the system, the module will control or carry out the relevant task.

3. A module according to claim 2 wherein the scheduling means may store the task data together with an indicator of status selected from at least two alternative statuses such as “

tentative” and

“

firm”

, said indicator of status determining a mode in which the scheduling means deals with the relevant task data.

4. A module according to claim 3 wherein the scheduling means operates a time-out in relation to task definition data having one of said indicators of status, after which the task definition data is deleted by the scheduling means.

5. A module according to claim 4 wherein the scheduling means may overbook resources by storing data from more than one task definition, said data storing overlapping time constraints in relation to the same resource or resources.