Method and device for partitioning a computer program

• US 7,103,879 B2
• Filed: 01/15/2002
• Issued: 09/05/2006
• Est. Priority Date: 01/16/2001
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Moreau, Jean-Jacques, Ruellan, Herve
• Primary Examiner(s): DAS, CHAMELI
• Application Number:
  US10/045,073
• Publication Number:
  US 20020124240A1
• Time in Patent Office: 1,694 Days
• Field of Search: 717/107, 717/108, 717/104, 717/130, 717168-173, 717/131, 717/140, 717/103, 718/106, 709/201, 709/245, 709/246, 709/232, 719/315
• US Class Current: 717/130
• CPC Class Codes: G06F 9/5066 Algorithms for mapping a plurality of inter-dependent sub-tasks onto a plurality of physical CPUs mappping at compile time, see G06F8/451

Abstract

The invention concerns a method of partitioning a computer program situated on a first processing site, the program containing subprograms able to transfer information, characterised in that it includes a step of automatic determination, for at least one of said subprograms, of data representing the transfer of at least part of the information processed by said subprogram, and a step of allocating said subprogram to a second processing site according to said data.

Claims

1. A method of partitioning a computer program situated on a first processing site, the program containing subprograms able to transfer information, and the program comprising:

a step of automatic determination, for at least one of the subprograms, of data representing the transfer of at least part of the information processed by that subprogram, said automatic determination step comprising;

a substep of modifying source code of the computer program, during which substep are inserted in source code of at least one subprogram of the computer program;

first lines of instructions making it possible, when they are executed, to obtain and store a reference of a subprogram calling that subprogram; and

second lines of instructions making it possible, when they are executed, to obtain and store the total of the data representing the information received or transferred by that subprogram;

a substep of compiling the modified source code and generating a modified program; and

a substep of obtaining the representative data by means of at least one execution of the modified program;

and a step of allocating the subprogram to a second processing site according to the data.

2. A method according to claim 1, wherein said substep of modifying the source code includes replacing, in source code of at least one subprogram of the computer program, calls to low-level functions by lines of instructions making it possible, when they are executed, to obtain and store if the data transferred by said subprogram are situated on a distant storage site.

3. A method according to claim 1, wherein the representative data are obtained statistically, after at least two executions of the modified computer program.

4. A method according to claim 1, wherein the data represent a quantity of the part of the information processed by the subprogram.

5. A method according to claim 1, wherein the data represent a transfer time of the part of the information processed by the subprogram.

6. A method according to claim 1, wherein the data represent characteristics of a transmission channel between the first processing site and the second processing site.

7. A method according to claim 6, wherein the data representing the transmission channel are chosen from among latency, bandwidth, error rate, mean load on the transmission channel and at least one value dependent on a protocol for communicating the part of the information between the first processing site and the second processing site.

8. A method according to claim 1, wherein said allocation step is performed so as to minimize, by analysis of the representative data, the transfer of information between the first processing site and the second processing site.

9. A computer, comprising means adapted to implement the method according to any one of claims 1 to 8.

10. An information storage medium which can be read by a computer or by a microprocessor storing instructions of a computer program, making it possible to implement a partitioning method according to any one of claims 1 to 8.

11. The information storage medium according to claim 10, said storage medium being a removable one.

12. A device for partitioning a computer program situated on a first processing site, the program containing subprograms able to transfer information, comprising:

means of automatic determination, for at least one of the subprograms, of data representing the transfer of at least part of the information processed by that subprogram, said automatic determination means including;

means for modifying source code of the computer program, said means being adapted to insert in source code of at least one sub-program of the computer program;

first lines of instructions making it possible, when executed, to obtain and store a reference of a subprogram calling that subprogram; and

second lines of instructions making it possible, when executed, to obtain and store the total of the data representing the information received or transferred by that subprogram;

means for compiling the modified source code and generating a modified program; and

means adapted to obtain the representative data by at least one execution of the modified program; and

means for allocating the subprogram to a second processing site according to the data.

13. A partitioning device according to claim 12, wherein said means of modifying the source code replace, in the source code of at least one subprogram of the computer program, calls to low-level functions by lines of instructions making it possible, when executed, to obtain and store if the data transferred by that subprogram are stored on a distant storage site.

14. A partitioning device according to claim 12, wherein said means adapted to obtain the representative data operate statistically, after at least two executions of the modified computer program.

15. A partitioning device according to claim 12, said device being adapted to consider data representing a quantity of the part of the information processed by the subprogram.

16. A partitioning device according to claim 12, said device being adapted to consider data representing a transfer time for the part of the information processed by the subprogram.

17. A partitioning device according to claim 12, said device being adapted to consider data representing characteristics of a transmission channel between the first processing site and the second processing site.

18. A partitioning device according to claim 17, said device being adapted to consider data representing the transmission channel chosen from among latency, passband, error rate, mean load on the transmission channel and at least one value dependent on a protocol for communicating the part of the information between the first processing site and the second processing site.

19. A partitioning device according to claim 12, wherein said allocation means are adapted to minimize, by analysis of the representative data, the transfer of information between the first processing site and the second processing site.

20. A partitioning device according to claim 12, wherein said automatic determination and allocation means are incorporated in:

a central unit,

a read only memory containing instructions relating to implementation of the partitioning; and

a random access memory containing registers adapted to record variables modified during the execution of the instructions.

21. A computer, comprising a device according to any one of claims 12 to 20.