Adaptive spinning of computer program threads acquiring locks on resource objects by selective sampling of the locks

• US 8,621,464 B2
• Filed: 01/31/2011
• Issued: 12/31/2013
• Est. Priority Date: 01/31/2011
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Dawson, Michael H., Sundaresan, Vijay V., Svikine, Alexei I.
• Primary Examiner(s): Puente, Emerson
• Assistant Examiner(s): Huaracha, Willy W
• Application Number:
  US13/017,848
• Publication Number:
  US 20120198454A1
• Time in Patent Office: 1,065 Days
• Field of Search: 718/100, 718/102, 718/101, 718/104, 710/200
• 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 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 spinning;

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; and

terminating the monitoring of said values of said first set of parameters of said lock while threads currently spinning continue spinning.

2. The method of claim 1, wherein said first and second sets of parameters have at least one common parameter.

3. The method of claim 1, wherein:

said monitoring of said values of said first set of parameters monitors said first set of each at 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.

4. The method of claim 3, wherein:

said second set of parameters is predetermined; and

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

5. The method of claim 4, 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.

6. The method of claim 3, wherein one of said second set of parameter values is to hold time for a spinning thread for acquiring the requester lock.

7. 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 which 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 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 spinning;

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; and

terminating the monitoring of said values of said first set of parameters of said lock while threads currently spinning continue spinning.

8. The system of claim 7, wherein said first and second sets of parameters have at least one common parameter.

9. The system of claim 7, 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.

10. The system of claim 9, wherein:

said second set of parameters is predetermined; and

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

11. The system of claim 10, 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.

12. The system of claim 9, wherein one of said second set of parameter values is the hold time for a spinning thread for acquiring the requested lock.

13. A computer usable nod-transitory 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 spinning;

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

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

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; and

terminate the monitoring of said values of said first set of first parameters of said lock while threads currently spinning continue spinning.

14. The computer usable non-transitory storage medium of claim 13, wherein said first and second sets of parameters have at least one common parameter.

15. The computer usable non-transitory storage medium of claim 13, wherein said computer readable program when executed on a computer:

monitors said values of said first set of parameters by monitoring said first set parameter values 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.

16. The computer usable non-transitory storage medium of claim 15, wherein:

said second set of parameters is predetermined; and

and said values of said second set of parameters is initially applied to predetermine whether each of said plurality of locks should he monitored.

17. The computer usable non-transitory storage medium of claim 16, 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.

18. The computer usable non-transitory storage medium of claim 16, wherein ore of said second set of parameter values is the hold time for a spinning thread acquiring the requested lock.