PROCESSING SYSTEM INCLUDING A PLURALITY OF CORES AND METHOD OF OPERATING THE SAME

• US 20140196050A1
• Filed: 10/24/2013
• Published: 07/10/2014
• Est. Priority Date: 01/07/2013
• Status: Active Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Ki Soo Yu
• Inventors: YU, Ki Soo, SUN, KYUNG IL, YOUN, Chang Hwan
• Granted Patent: US 10,255,118 B2
• Time in Patent Office: Days
• US Class Current: 718/104
• CPC Class Codes: G06F 2209/5022 Workload threshold
• CPC Class Codes: G06F 9/5088 involving task migration
• CPC Class Codes: G06F 9/5094 where the allocation takes into account power or heat criteria power management in computers in general G06F1/3203; thermal management in computers in general G06F1/206
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A system and method of allocating resources among cores in a multi-core system is disclosed. The system and method determine cores that are able to process tasks to be performed, and use history of usage information to select a core to process the tasks. The system may be a heterogeneous multi-core processing system, and may include a system on chip (SoC).

Claims

1. A method of assigning resources in a heterogeneous multi-core processing system including a plurality of first-type cores having a first architecture and a plurality of second-type cores having a second architecture different from the first architecture, the method comprising:

maintaining history of usage information for each core of the plurality of first-type cores and each core of the plurality of second-type cores;

receiving a request to perform a task;

selecting a core from among the plurality of first-type cores and the plurality of second-type cores to perform the task,

wherein the selecting depends at least in part on the history of usage information.

2. A method of claim 1, wherein selecting a core from among the plurality of first-type cores and the plurality of second-type cores to perform the task includes:

determining whether a first core of the plurality of first-type cores has sufficient resources available to perform the task; and

when it is determined that the first core does not have sufficient resources available to perform the task, selecting a second core from among the plurality of first-type cores and the plurality of second-type cores to perform the task, based at least in part on the history of usage information.

3. The method of claim 2, wherein:

the first core is a core having a first size; and

the second core is a core having a second size larger than the first size.

4. The method of claim 1, wherein:

the selecting depends at least in part on one or more of the following;

a selection count number indicating a number of times a core has been selected;

a usage time indicating an amount of past usage time of the core;

an instruction count number indicating a number of instructions executed by the core; and

a core load count number indicating a historical load amount processed by the core.

5. The method of claim 1, wherein:

the selecting depends at least in part on an occupied or unoccupied state of the plurality of first-type cores and plurality of second-type cores.

6. The method of claim 5, further comprising:

prior to the selecting, excluding from selection at least one core determined to be in an unoccupied state.

7. The method of claim 1, further comprising:

determining that a core of the plurality of first-type cores has sufficient resources to process all of the tasks being performed on a core of the plurality of second-type cores; and

as a result of the determination, moving the tasks being performed on the core of the plurality of second-type cores to the core of the plurality of first-type cores.

8. The method of claim 7, further comprising:

after the moving step, powering down the core of the plurality of second-type cores.

9. The method of claim 1, wherein:

the plurality of first-type cores are part of a first cluster of processors; and

the plurality of second-type cores are part of a second cluster of processors.

10. The method of claim 1, further comprising:

storing the history of usage information in a history buffer,

wherein the history buffer initially has no history of usage information stored, and

for each core of the heterogeneous multi-core system, as a result of the core being accessed, a history of usage information indicating a number of times that core has been accessed is updated.

11. A method of assigning resources in a multi-core processing system including a plurality of first-sized cores and a plurality of second-sized cores, the first size being smaller than the second size, the method comprising:

maintaining history of usage information for each core of the plurality of first-sized cores and each core of the plurality of second-sized cores;

receiving a request to perform a task;

determining that a first core of the plurality of first-sized cores has insufficient resources to perform the task; and

as a result of the determination, selecting a second core from among the plurality of second-sized cores to perform the task,

wherein the selecting depends at least in part on the history of usage information.

12. The method of claim 11, wherein the first core is a core having a first maximum processing speed and the second core is a core having a second maximum processing speed greater than the first maximum processing speed.

13. The method of claim 11, wherein the first core includes transistors having a first size, and the second core includes transistors having a second size larger than the first size.

14. The method of claim 11, wherein:

the second core is selected from among the plurality of second-sized cores based at least in part on one or more of the following;

a selection count number indicating a number of times a core has been selected;

a usage time indicating an amount of past usage time of the core;

an instruction count number indicating a number of instructions executed by the core; and

a core load count number indicating a historical load amount processed by the core.

15. The method of claim 11, further comprising:

storing a history log that includes the history of usage information; and

updating the history log when a particular core is selected to perform a task, to reflect the selection.

16. The method of claim 15, further comprising:

upon selection of the particular core, updating the history log to increase a selection count number for the particular core indicating a number of times that core has been selected.

17. The method of claim 16, wherein the selection count number for the particular core reflects a lifetime usage for that core.

18. The method of claim 15, further comprising:

upon selection of the particular core, updating a status flag to indicate that the particular core is in an occupied state.

19. A method of assigning resources in a multi-core processing system including a plurality of first-sized cores and a plurality of second-sized cores, the first size being smaller than the second size, the method comprising:

storing history of usage information for each core of the plurality of first-sized cores and each core of the plurality of second-sized cores;

determining a set of cores of the plurality of first-sized cores that each individually have sufficient resources to process all of the processes being performed on a core of the plurality of second-sized cores; and

selecting at least a first core of the set of cores based at least in part on the history of usage information,

wherein the first core is selected from among the set of cores based at least in part on one or more of the following;

a selection count number indicating a number of times the first core has been selected;

a usage time indicating an amount of past usage time of the first core;

an instruction count number indicating a number of instructions executed by the first core; and

a core load count number indicating a historical load amount processed by the first core.

20. The method of claim 19, further comprising:

as a result of the selecting, moving the processes being performed on the core of the plurality of second-sized cores to the selected at least first core.

21. The method of claim 19, wherein the plurality of first-sized cores are cores having a first type of architecture and the plurality of second-sized cores are cores having a second type of architecture different from the first type.

22. A resource management controller for assigning resources among a plurality of cores in a heterogeneous multi-core processing system including a plurality of first cores and a plurality of second cores different from the first cores, the controller comprising:

a determining circuit configured to determine whether a first core of the plurality of first cores has sufficient resources available to perform a requested task; and

a selecting circuit configured to, when it is determined that the first core does not have sufficient resources to perform the task, select a second core from among the plurality of first cores and the plurality of second cores to perform the task,

wherein the selecting depends at least in part on history information reflecting a history of usage of the plurality of first cores and plurality of second cores.

23. The resource management controller of claim 22, wherein:

the first core has a first size, and the second core has a second size larger than the first size.

24. The resource management controller of claim 22, wherein:

the first core has a first maximum processing speed, and the second core has a second maximum processing speed greater than the first maximum processing speed.

25. The resource management controller of claim 22, wherein:

the resource management controller comprises hardware and software.

26. The resource management controller of claim 22, further comprising:

a history log storing the history information.

27. A heterogeneous multi-core processing system, comprising:

a plurality of core processors including a plurality of first-speed core processors each having a first maximum speed and a plurality of second-speed core processors each having a second maximum speed faster than the first speed; and

a controller coupled to the plurality of core processors, wherein the controller is configured to;

select a first second-speed core processor based on a history of usage of the plurality of second-speed core processors;

assign one or more tasks to the first second-speed core processor in response to a determination that a load on a first first-speed core processor of the plurality of first-speed core processors is above a first threshold load amount;

select one of the plurality of first-speed core processors based on a history of usage of the plurality of first-speed core processors; and

assign one or more tasks to the selected first-speed core processor in response to a determination that a load on the first second-speed core processor is below a second threshold load amount.

28. The processing system of claim 27, wherein:

each of the plurality of first-speed core processors is powered with a first voltage; and

each of the plurality of second-speed core processors is powered with a second voltage higher than the first voltage.

29. The processing system of claim 27, wherein:

the controller comprises hardware and software.

30. The processing system of claim 27, further comprising:

a history log storing information reflecting the history of usage of the plurality of the second-speed core processors and the history of usage of the plurality of first-speed core processors.

31. The processing system of claim 30, wherein:

the history log includes information for each of a plurality of core processors, the information reflecting one or more of;

a selection count number indicating a number of times the core processor has been selected;

a usage time indicating an amount of past usage time of the core processor;

an instruction count number indicating a number of instructions executed by the core processor; and

a core load count number indicating a historical load amount processed by the core processor.

32. A processing system comprising:

a plurality of first cores having a first size;

a plurality of second cores having a second size larger than the first size, the number of the plurality of first cores being different from the number of the plurality of second cores;

a controller coupled to the plurality of first cores and plurality of second cores;

a first history log coupled to the controller and coupled to the plurality of first cores; and

a second history log coupled to the controller and coupled to the plurality of second cores,

wherein the controller includes a first counter configured to count numbers of accesses to the first cores, and a second counter configured to count numbers of accesses to the second cores, and the controller is configured to;

receive an external request to perform a task; and

assign the task to a selected core from among the plurality of first cores and plurality of second cores, the selected core selected based on at least one of information stored in the first history log and information stored in the second history log.

33. The processing system of claim 32, wherein:

the controller comprises hardware and software.

34. The processing system of claim 32, wherein the controller is further configured to:

determine that none of the plurality of first cores are able to process the task, and as a result, assign the task to one of the plurality of second cores based on the information stored in the second history log.

35. The processing system of claim 32, wherein the controller is further configured to:

determine that a set of one or more tasks being performed on a second core of the plurality of second cores can be performed by a first core of the plurality of first cores; and

in response to the determination, move the set of one or more tasks to the first core.

36. A system on chip comprising:

a plurality of first cores;

a plurality of second cores different from the first cores; and

a controller, wherein the controller is configured to;

determine whether a first core of the plurality of first cores has sufficient resources available to perform a requested task; and

when it is determined that the first core does not have sufficient resources to perform the task, select a second core from among the plurality of first cores and the plurality of second cores to perform the task,

wherein the selecting depends at least in part on history information reflecting a history of usage of the plurality of first cores and plurality of second cores.

37. The system on chip of claim 36, wherein:

the plurality of first cores and plurality of second cores form a heterogeneous multi-core processing system.

38. The system on chip of claim 36, wherein the controller is further configured to:

determine whether a first-sized core of the plurality of first cores has sufficient resources to perform all tasks being performed by a second-sized core of the plurality of second cores, the first size being smaller than the second size; and

when it is determined that the first-sized core has sufficient resources to perform all tasks being performed by the second-sized core, moving all tasks being performed by the second-sized core to the first-sized core.