Opportunistic Multitasking

• US 20110252430A1
• Filed: 08/26/2010
• Published: 10/13/2011
• Est. Priority Date: 04/07/2010
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Schreyer, Richard, Chapman, Gregory R., Duffy, Thomas B. JR.
• Application Number:
  US12/869,553
• Publication Number:
  US 20110252430A1
• Time in Patent Office: Days
• US Class Current: 718/107
• CPC Class Codes: G06F 9/485 Task life-cycle, e.g. stopping, restarting, resuming execution G06F9/4881 takes precedence
• CPC Class Codes: G06F 9/5011 the resources being hardware resources other than CPUs, Servers and Terminals
• CPC Class Codes: G06F 9/542 Event management; Broadcasting; Multicasting; Notifications

Abstract

Services for a personal electronic device are provided through which a form of background processing or multitasking is supported. The disclosed services permit user applications to take advantage of background processing without significant negative consequences to a user'"'"'s experience of the foreground process or the personal electronic device'"'"'s power resources. To effect the disclosed multitasking, one or more of a number of operational restrictions may be enforced. By way of example, an application that may normally be placed into the background state may instead be terminated if it controls a lock on a shared system resource.

Claims

1. A multitasking method, comprising:

identifying a first user application executing in a foreground state;

receiving user input directing that a second application is to be placed into the foreground state;

terminating the first user application if said first user application has at least one lock on a shared system resource, else placing the first user application in a background state in response to the received user input only if the first user application has identified itself as a user application that can execute in the background state; and

placing the second application into the foreground state.

2. The method of claim 1, further comprising scheduling the first user application, after the first user application has been placed into the background state, to use a processor in accordance with a priority level, the priority level being selected from a band of priority levels that overlap with some, but not all, priority levels assigned to foreground processes.

3. The method of claim 1, further comprising terminating the first user application, after the first user application has been placed into the background state, if the first user application attempts to execute instructions targeted for a specified hardware resource.

4. The method of claim 3, wherein the specified hardware resource comprises a graphics processing unit.

5. The method of claim 1, further comprising not executing instructions for the first user application, once the first user application is in the background state, if the instructions are directed to changing a display memory.

6. The method of claim 1, wherein the shared system resource comprises a shared file descriptor.

7. The method of claim 1, wherein the act of placing the second application into the foreground state comprises placing an operating system application into the foreground state.

8. A program storage device, readable by a programmable control device, comprising instructions stored thereon for causing the programmable control device to perform a method in accordance with claim 1.

9. A personal electronic device, comprising:

memory;

a programmable control device operatively coupled to the memory, said programmable control device configured to execute instructions, stored in the memory, to—

identify a first user application executing in a foreground state;

receive user input directing that a second application is to be placed into the foreground state;

terminate the first user application if said first user application has at least one lock on a shared system resource, else placing the first user application in a background state in response to the received user input only if the first user application has identified itself as a user application that can execute in the background state; and

place the second application into the foreground state.

10. The personal electronic device of claim 9 comprising a personal electronic device selected from the group consisting of:

a mobile telephone, a personal digital assistant, a hand-held entertainment device, a pad computer system and a set top box.

11. The personal electronic device of claim 9, wherein the second application comprises a second user application.