ADAPTIVE SPINNING OF COMPUTER PROGRAM THREADS ACQUIRING LOCKS ON RESOURCE OBJECTS BY SELECTIVE SAMPLING OF THE LOCKS

• US 20120198454A1
• Filed: 01/31/2011
• Published: 08/02/2012
• Est. Priority Date: 01/31/2011
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Dawson, Michael H., Sundaresan, Vijay V., Svikine, Alexei I.
• Granted Patent: US 8,621,464 B2
• Time in Patent Office: Days
• US Class Current: 718/100
• CPC Class Codes: G06F 2209/508 Monitor
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms

Abstract

In the dynamic sampling or collection of data relative to locks for which threads attempting to acquire the lock may be spinning so as to adaptively adjust the spinning of threads for a lock, an implementation for monitoring a set of parameters relative to the sampling of data of particular locks and selectively terminating the sampling when certain parameter values or conditions are met.

Claims

1. A method for adjusting the spinning of computer process threads awaiting locks on objects in data processing systems comprising:

monitoring values of a first set of parameters of a lock on an object, for which lock, threads requesting said lock are capable of spinning;

applying said monitored values of said first set of parameters to adjust the spinning of said threads requesting said lock;

monitoring values of a second set of parameters relative to said lock on an object, for which lock, threads requesting said lock are capable of spinning; and

applying said values of said second set of parameters to determine whether the monitoring of said first set of parameters of said lock should be terminated.

2. The method of claim 1 further including terminating the monitoring of said values of said first set of parameters of said lock while threads currently spinning continue spinning.

3. The method of claim 2, wherein said first and second sets of parameters have at least one common parameter.

4. The method of claim 2, wherein:

said monitoring of said values of said first set of parameters monitors said first set of each of a plurality of locks on objects; and

the monitoring of the values of said first set of parameters of at least one lock is terminated.

5. The method of claim 4, wherein:

said second set of parameters is predetermined; and

said values of said second set of parameters are initially applied to predetermine whether each of said plurality of locks should be monitored.

6. The method of claim 5, wherein one of said second set of parameters is whether said lock has had to use a lower level lock than an initially requested lock at least once.

7. The method of claim 4, wherein one of said second set of parameter values is the hold time for a spinning thread for acquiring the requested lock.

8. A system for adjusting the spinning of computer process threads awaiting locks on objects in data processing, said system comprising:

a processor; and

a computer memory holding computer program instructions that, when executed by the processor, perform the method comprising;

monitoring values of a first set of parameters of a lock on an object, for which lock threads requesting said lock are capable of spinning;

applying said monitored values of said first set of parameters to adjust the spinning of said threads requesting said locks;

monitoring values of a second set of parameters relative to said lock on an object, for which lock threads requesting said lock are capable of spinning; and

applying said values of said second set of parameters to determine whether the monitoring of said first set of parameters of said lock should be terminated.

9. The system of claim 8, wherein said performed method further includes terminating the monitoring of said values of said first set of parameters of said lock while threads currently spinning threads continue spinning.

10. The system of claim 9, wherein said first and second sets of parameters have at least one common parameter.

11. The system of claim 9, wherein:

said monitoring of said values of said first set of parameters monitors said first set of each of a plurality of locks on objects; and

the monitoring of the values of said first set of parameters of at least one lock is terminated.

12. The system of claim 11, wherein:

said second set of parameters is predetermined; and

said values of said second set of parameters are initially applied to predetermine whether each of said plurality of locks should be monitored.

13. The system of claim 12, wherein one of said second set of parameters is whether said lock has had to use a lower level lock than an initially requested lock at least once.

14. The system of claim 11, wherein one of said second set of parameter values is the hold time for a spinning thread for acquiring the requested lock.

15. A computer usable storage medium having stored thereon a computer readable program for adjusting the spinning of computer process threads awaiting locks on objects in a data processing system, wherein the computer readable program, when executed on a computer, causes the computer to:

monitor values of a first set of parameters of a lock on an object, for which lock threads requesting said lock are capable of spinning;

apply said monitored values of said first set of parameters to adjust the spinning of said threads requesting said lock;

monitor values second set of parameters relative to said lock on an object, for which lock, threads requesting said lock are spinning; and

apply said values of said second set of parameters to determine whether the monitoring of said first set of parameters of said lock should be terminated.

16. The computer usable medium of claim 15, wherein said computer program, when executed on a computer, further causes the computer to terminate the monitoring of said values of said first set of parameters of said lock while threads currently spinning continue spinning.

17. The computer usable medium of claim 16, wherein said first and second sets of parameters have at least one common parameter.

18. The computer usable medium of claim 16, wherein said computer readable program, when executed on a computer:

monitors said values of said first set of parameters by monitoring said first set of parameter values of each of a plurality of locks on objects; and

monitoring of the values of said first set of parameters of at least one lock is terminated.

19. The computer usable medium of claim 18, wherein:

said second set of parameters is predetermined; and

said values of said second set of parameters are initially applied to predetermine whether each of said plurality of locks should be monitored.

20. The computer usable medium of claim 19, wherein one of said second set of parameters is whether said lock has had to use a lower level lock than an initially requested lock at least once.

21. The computer usable medium of claim 19, wherein one of said second set of parameter values is the hold time for a spinning thread acquiring the requested lock.