System and method for improving run-time performance of applications with multithreaded and single threaded routines

• US 8,495,662 B2
• Filed: 09/23/2008
• Issued: 07/23/2013
• Est. Priority Date: 08/11/2008
• Status: Active Grant

• Current Assignee: Valtrus Innovations Limited (f/k/a Dolya Holdco 9 Limited) (Key Patent Innovations Limited)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Mannarswamy, Sandya Srivilliputtur, Saraswati, Sujoy, Raghavendra, Prakash Sathyanath
• Primary Examiner(s): Sough, H S
• Assistant Examiner(s): DORAIS, CRAIG C
• Application Number:
  US12/235,625
• Publication Number:
  US 20100037242A1
• Time in Patent Office: 1,764 Days
• Field of Search: None
• US Class Current: 719/328
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms

Abstract

A system and method for improving run-time performance of applications with multithreaded and single threaded routines that are linked with libpthreads library is disclosed. In one embodiment, a method for running a mixed ST/MT application program linked with libpthreads library including creating an interceptor library containing pthread application programming interface (pthread_API) call interceptors and loading the interceptor library into the mixed ST/MT application program, and running the mixed ST/MT application program by using light weight (LW) and heavy weight (HW) synchronization routines based on determining switchovers between ST and MT program modes, respectively, during run-time using the interceptor library.

Claims

1. A method for running a mixed single-threaded/multi-threaded (ST/MT) application program linked with a libpthreads library, the method comprising:

creating an interceptor library containing pthread application programming interface (pthread_API) call interceptors and loading the interceptor library into the mixed ST/MT application program;

incrementing or decrementing a thread counter upon each pthread_create call or pthread_exit call, respectively, during run-time;

triggering a helper thread upon decrementing the thread counter by a predetermined value, wherein the helper thread computes an estimated resulting overhead by determining a duration of time the mixed ST/MT application program runs in an ST program mode by examining sliced versions of the mixed ST/MT application program; and

running the mixed ST/MT application program on a computer by using light weight (LW) and heavy weight (HW) synchronization routines based on determining switchovers between the ST program mode and an MT program mode, respectively, during run-time using the interceptor library, the mixed ST/MT application program being run in the ST program mode by informing a pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the determined duration of time and the estimated resulting overhead, selection between the ST program mode and the MT program mode being based on a value in the thread counter.

2. The method of claim 1, wherein running the mixed ST/MT application program by using the LW and HW synchronization routines based on determining the switchovers between the ST and MT program modes comprises:

dynamically loading the interceptor library before loading other shared libraries into the mixed ST/MT application program; and

initializing the thread counter.

3. The method of claim 1, wherein running the mixed ST/MT application program comprises:

estimating a second resulting overhead due to the switchovers between the ST and MT program modes using statistical analysis or profile data including pthread API calls based on previous mixed ST/MT application program runs upon incrementing the thread counter by the predetermined value; and

running the mixed ST/MT application program in the ST program mode by informing the pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the estimated second resulting overhead.

4. The method of claim 3, wherein the statistical analysis or profile data including the pthread API calls is based on the duration of time during which the mixed ST/MT application program stays in the ST program mode during run-time and the estimated second resulting overhead.

5. A method for running a mixed single-threaded/multi-threaded (ST/MT) application program linked with a libpthreads library, the method comprising:

creating an interceptor library containing pthread application programming interface (pthread_API) call interceptors and loading the interceptor library into the mixed ST/MT application program; and

running the mixed ST/MT application program on a computer by using light weight (LW) and heavy weight (HW) synchronization routines based on determining switchovers between ST and MT program modes, respectively, during run-time using the interceptor library, running the mixed ST/MT application program by using the LW and HW synchronization routines based on determining the switchovers between the ST and MT program modes comprising;

dynamically loading the interceptor library before loading other shared libraries into the mixed ST/MT application program; and

initializing a thread counter by a predetermined value;

incrementing or decrementing the thread counter by the predetermined value upon each pthread_create call or pthread_exit call, respectively, during run-time; and

running the mixed ST/MT application program in the ST program mode by informing a pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on a value in the thread counter; and

running the mixed ST/MT application program comprising;

triggering a helper thread upon decrementing the thread counter by the predetermined value, wherein the helper thread computes an estimated resulting overhead by determining a duration of time the mixed ST/MT application program runs in the ST program mode by examining sliced versions of the mixed ST/MT application program; and

running the mixed ST/MT application program in the ST program mode by informing the pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the determined duration of time and the estimated resulting overhead, the resulting overhead and an expected percent of improvement being computed using the equations;

resulting overhead=number of locks to be converted*estimated overhead+helper thread overhead+pthread call overhead; and

expected percent of improvement=number of locks found during the period of time the mixed ST/MT application program runs in the ST program mode*estimated overhead for HW per lock.

6. A method for running a mixed single-threaded/multi-threaded (ST/MT) application program linked with a libpthreads library, the method comprising:

creating the libpthreads library including an interceptor library containing (API) call interceptors and loading the libpthreads library into the mixed ST/MT application program;

incrementing or decrementing a thread counter upon each pthread_create call or pthread_exit call, respectively, during run-time;

triggering a helper thread upon decrementing the thread counter by a predetermined value, wherein the helper thread computes an estimated resulting overhead by determining a duration of time the mixed ST/MT application program runs in an ST program mode by examining sliced versions of the mixed ST/MT application program; and

running the mixed ST/MT application program on a computer by using LW and HW synchronization routines based on determining switchovers between the ST program mode and an MT program mode, respectively, during run-time using the interceptor library, the mixed ST/MT application program being run in the ST program mode by informing a pthreads library to call the LW synchronization routines, or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the determined duration of time and the estimated resulting overhead, selection between the ST program mode and the MT program mode being based on a value in the thread counter.

7. The method of claim 6, wherein running the mixed ST/MT application program by using the LW and HW synchronization routines based on determining the switchovers between the ST and MT program modes comprises:

loading the libpthreads library into the mixed ST/MT application program; and

initializing the thread counter.

8. The method of claim 6, wherein running the mixed ST/MT application program comprises:

estimating a second resulting overhead due to the switchovers between the ST and MT program modes using statistical analysis or profile data including pthread API calls based on previous mixed ST/MT application program runs upon incrementing the thread counter by the predetermined value; and

running the mixed ST/MT application program in the ST program mode by informing the pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the estimated second resulting overhead due to the switchovers between the ST and MT program modes.

9. A computer readable storage medium comprising instructions which, when executed by a computer, cause the computer to run a mixed ST/MT program linked with libpthreads library, the instructions comprising:

creating an interceptor library containing pthread application programming interface (pthread_API) call interceptors and loading the interceptor library into the mixed ST/MT application program;

incrementing or decrementing a thread counter upon each pthread_create call or pthread_exit call, respectively, during run-time;

triggering a helper thread upon decrementing the thread counter by a predetermined value, wherein the helper thread computes an estimated resulting overhead by determining a duration of time the mixed ST/MT application program runs in an ST program mode by examining sliced versions of the mixed ST/MT application program; and

running the mixed ST/MT application program by using LW and HW synchronization routines based on determining switchovers between the ST program mode and an MT program mode, respectively, during run-time using the interceptor library, the mixed ST/MT application program being run in the ST program mode by informing a pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the determined duration of time and the estimated resulting overhead, selection between the ST program mode and the MT program mode being based on a value in the thread counter.

10. The storage medium of claim 9, wherein running the mixed ST/MT application program by using the LW and HW synchronization routines based on determining the switchovers between the ST and MT program modes comprises:

dynamically loading the interceptor library before loading other shared libraries into the mixed ST/MT application program; and

initializing the thread counter.

11. The article storage medium of claim 9, wherein running the mixed ST/MT application program comprises:

estimating a second resulting overhead due to the switchovers between the ST and MT program modes using statistical analysis or profile data including pthread API calls based on previous mixed ST/MT application program runs upon incrementing the thread counter by the predetermined value; and

running the mixed ST/MT application program in the ST program mode by informing the pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the estimated second resulting overhead.

12. A computer system comprising:

a processor; and

a memory in communication with the processor, the memory to store instructions which, when executed by the processor, cause the processor to perform a method of running a mixed ST/MT application program linked with a libpthreads library, the method comprising;

creating an interceptor library containing pthread application programming interface (pthread_API) call interceptors and loading the interceptor library into the mixed ST/MT application program;

incrementing or decrementing a thread counter upon each pthread_create call or pthread_exit call, respectively, during run-time;

triggering a helper thread upon decrementing the thread counter by a predetermined value, wherein the helper thread computes an estimated resulting overhead by determining a duration of time the mixed ST/MT application program runs in an ST program mode by examining sliced versions of the mixed ST/MT application program; and

running the mixed ST/MT application program by using LW and HW synchronization routines based on determining switchovers between the ST program mode and an MT program mode, respectively, during run-time using the interceptor library, the mixed ST/MT application program being run in the ST program mode by informing a pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the determined duration of time and the estimated resulting overhead, selection between the ST program mode and the MT program mode being based on a value in the thread counter.

13. The system of claim 12, wherein running the mixed ST/MT application program by using the LW and HW synchronization routines based on determining the switchovers between the ST and MT program modes comprises:

dynamically loading the interceptor library before loading other shared libraries into the mixed ST/MT application program; and

initializing the thread counter.

14. The system of claim 12, wherein running the mixed ST/MT application program comprises:

estimating a second resulting overhead due to the switchovers between the ST and MT program modes using statistical analysis or profile data including pthread API calls based on previous mixed ST/MT application program runs upon incrementing the thread counter by the predetermined value; and

running the mixed ST/MT application program in the ST program mode by informing pthreads library to call the LW synchronization routines or in the MT program mode by informing the pthreads library to call the HW synchronization routines based on the estimated second resulting overhead.