Method, system and program products for managing thread pools of a computing environment to avoid deadlock situations by dynamically altering eligible thread pools

• US 6,898,617 B2
• Filed: 11/18/1999
• Issued: 05/24/2005
• Est. Priority Date: 11/18/1999
• Status: Expired due to Fees

• Current Assignee: Daedalus Blue LLC
• Original Assignee: International Business Machines Corporation
• Inventors: Krein, Timothy Peter, Doolittle, Gregory David, Marcotte, Scott Thomas
• Primary Examiner(s): Dharia, Rupal
• Assistant Examiner(s): WILLETT, STEPHAN F
• Application Number:
  US09/443,202
• Publication Number:
  US 20020194377A1
• Time in Patent Office: 2,014 Days
• Field of Search: 717/172, 717/173, 717/174, 717/177, 717/178, 709/102, 709/106, 709/201, 709/202, 709/226, 709/332, 709/104, 709/313, 709/317
• US Class Current: 709/201
• CPC Class Codes: G06F 2209/5011 Pool
• CPC Class Codes: G06F 2209/5013 Request control
• CPC Class Codes: G06F 2209/5018 Thread allocation
• CPC Class Codes: G06F 9/5027 the resource being a machine, e.g. CPUs, Servers, Terminals

Abstract

Deadlock situations within a computing environment are avoided by properly managing pools of threads used to service requests of the computing environment. When a server of the computing environment receives a request to be processed and that request is waiting on a response from a client of the computing environment, the set of eligible thread pools for the response is dynamically altered. This dynamic altering allows the response to be serviced by a thread pool different from the thread pool servicing the request, thereby avoiding a deadlock situation.

Claims

1. A method of managing thread pools of a computing environment, said method comprising:

receiving from a first requester of said computing environment a request to be processed, said request waiting on a response from a second requester of said computing environment, and wherein said response is to be serviced by a thread pool selected from a set of one or more eligible thread pools;

upon receipt of the request waiting on the response, and without input from said first requester or said second requester of which thread pools can service the response, dynamically altering said set of one or more eligible thread pools to provide an altered thread pool set of eligible thread pools, wherein a thread pool of the altered thread pool set is to service said response to avoid a deadlock with said request awaiting said response;

wherein said dynamically altering comprises setting a pool mask to indicate said eligible thread pools of said altered thread pool set to service said response; and

wherein said receiving comprises receiving said request by a server of said computing environment, and wherein said first requester is a first client and said second requester is a second client.

2. The method of claim 1, wherein said pool mask is included within a data structure associated with said response.

3. The method of claim 1, wherein said dynamically altering is initiated when it is determined that said request is waiting for said response.

4. The method of claim 1, further comprising dynamically re-altering said altered thread pool set to service one or more other responses or one or more other requests.

5. The method of claim 4, wherein said dynamically re-altering is performed when there are no outstanding callbacks to be responded to by said second requester.

6. The method of claim 5, further comprising determining whether there are any outstanding callbacks, said determining referencing a data structure associated with said second requester.

7. The method of claim 1, wherein said server is a file server.

8. The method of claim 1, wherein at least one of said first client and said second client runs on a same physical computer of said computing environment as said server.

9. The method of claim 1, wherein at least one of said first client and said second client runs on a different physical computer of said computing environment than said server.

10. The method of claim 1, wherein said dynamically altering is performed by a server of said computing environment.

11. The method of claim 1, wherein said first requester and said second requester are the same requester.

12. The method of claim 1, wherein said first requester and said second requester are different requesters.

13. A system of managing thread pools of a computing environment, said system comprising:

means for receiving from a first requester of said computing environment a request to be processed, said request waiting on a response from a second requester of said computing environment, and wherein said response is to be serviced by a thread pool selected from a set of one or more eligible thread pools;

means for, upon receipt of the request waiting on the response, and without input from said first requester or said second requester of which thread pools can service the response, dynamically altering said set of one or more eligible thread pools to provide an altered thread pool set of eligible thread pools, wherein a thread pool of the altered thread pool set is to service said response to avoid a deadlock with said request awaiting said response;

wherein said means for dynamically altering comprises means for setting a pool mask to indicate said eligible thread pools of said altered thread pool set to service said response; and

wherein said means for receiving comprises means for receiving said request by a server of said computing environment, and wherein said first requester is a first client and said second requester is a second client.

14. The system of claim 13, wherein said pool mask is included within a data structure associated with said response.

15. The system of claim 13, wherein the dynamically altering is initiated when it is determined that said request is waiting for said response.

16. The system of claim 13, further comprising means for dynamically re-altering said altered thread pool set to service one or more other responses or one or more other requests.

17. The system of claim 16, wherein said means for dynamically re-altering is performed when there are no outstanding callbacks to be responded to by said second requester.

18. The system of claim 17, further comprising means for determining whether there are any outstanding callbacks, said determining referencing a data structure associated with said second requester.

19. The system of claim 13, wherein said server is a file server.

20. The system of claim 13, wherein at least one of said first client and said second client runs on a same physical computer of said computing environment as said server.

21. The system of claim 13, wherein at least one of said first client and said second client runs on a different physical computer of said computing environment than said server.

22. The system of claim 13, wherein the dynamically altering is performed by a server of said computing environment.

23. The system of claim 13, wherein said first requester and said second requester are the same requester.

24. The system of claim 13, wherein said first requester and said second requester are different requesters.

25. A system of managing thread pools of a computing environment, said system comprising:

a processor adapted to receive from a first client of said computing environment a request to be processed, said request waiting on a response from a second client of said computing environment, and wherein said response is to be serviced by a thread pool selected from a set of one or more eligible thread pools;

said processor being adapted to, upon receipt of the request waiting on the response, and without input from said first client or said second client of which thread pools can service the response, dynamically alter said set of one or more eligible thread pools to provide an altered thread pool set of eligible thread pools, wherein a thread pool of the altered thread pool set is to service said response to avoid a deadlock with said request awaiting said response;

said processor being adapted to set a pool mask to indicate said eligible thread pools of said altered thread pool set to service said response; and

wherein said processor comprises a server of said computing environment.

26. The system of claim 25, wherein said first client and said second client are the same client.

27. The system of claim 25, wherein said first client and said second client are different clients.

28. At least one program storage device readable by a machine, tangibly embodying at least one program of instructions executable by the machine to perform a method of managing thread pools of a computing environment, said method comprising:

receiving from a first requester of said computing environment a request to be processed, said request waiting on a response from a second requester of said computing environment, and wherein said response is to be serviced by a thread pool selected from a set of one or more eligible thread pools;

upon receipt of the request waiting on the response, and without input from said first requester or said second requester of which thread pools can service the response, dynamically altering said set of one or more eligible thread pools to provide an altered thread pool set of eligible thread pools, wherein a thread pool of the altered thread pool set is to service said response to avoid a deadlock with said request awaiting said response;

wherein said dynamically altering comprises setting a pool mask to indicate said eligible thread pools of said altered thread pool set to service said response; and

wherein said receiving comprises receiving said request by a server of said computing environment, and wherein said first requester is a first client and said second requester is a second client.

29. The at least one program storage device of claim 28, wherein said pool mask is included within a data structure associated with said response.

30. The at least one program storage device of claim 28, wherein said dynamically altering is initiated when it is determined that said request is waiting for said response.

31. The at least one program storage device of claim 28, wherein said method further comprises dynamically re-altering said altered thread pool set to service one or more other responses or one or more other requests.

32. The at least one program storage device of claim 31, wherein said dynamically re-altering is performed when there are no outstanding callbacks to be responded to by said second requester.

33. The at least one program storage device of claim 32, wherein said method further comprises determining whether there are any outstanding callbacks, said determining referencing a data structure associated with said second requester.

34. The at least one program storage device of claim 33, wherein said ordering comprises having a primary thread pool selectable before any secondary thread pool.

35. The at least one program storage device of claim 28, wherein said server is a file server.

36. The at least one program storage device of claim 28, wherein at least one of said first client and said second client runs on a same physical computer of said computing environment as said server.

37. The at least one program storage device of claim 28, wherein at least one of said first client and said second client runs on a different physical computer of said computing environment than said server.

38. The at least one program storage device of claim 28, wherein said dynamically altering is performed by a server of said computing environment.

39. The at least one program storage device of claim 28, wherein said first requester and said second requester are the same requester.

40. The at least one program storage device of claim 28, wherein said first requester and said second requester are different requesters.