Multiple computer architecture with synchronization

• US 20060020913A1
• Filed: 04/22/2005
• Published: 01/26/2006
• Est. Priority Date: 04/23/2004
• Status: Active Grant

• Current Assignee: Waratek Limited (Waratek Holdings Ltd.)
• Original Assignee: Waratek Pty Limited
• Inventors: Holt, John M.
• Granted Patent: US 7,707,179 B2
• Time in Patent Office: Days
• US Class Current: 717/104
• CPC Class Codes: G06F 12/00 Accessing, addressing or allocating within memory systems or architectures digital input from, or digital output to record carriers, e.g. to disk storage units, G06F3/06
• CPC Class Codes: G06F 8/75 Structural analysis for program understanding
• CPC Class Codes: G06F 9/445 Program loading or initiating bootstrapping G06F9/4401; security arrangements for program loading or initiating G06F21/57
• CPC Class Codes: G06F 9/45504 Abstract machines for programme code execution, e.g. Java virtual machine [JVM], interpreters, emulators
• CPC Class Codes: G06F 9/46 Multiprogramming arrangements
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores

Abstract

The present invention discloses a modified computer architecture (50, 71, 72) which enables an applications program (50) to be run simultaneously on a plurality of computers (M1, . . . Mn). Shared memory at each computer is updated with amendments and/or overwrites so that all memory read requests are satisfied locally. During initial program loading (75), or similar, instructions which result in the application program (50) acquiring (or releasing) a lock on a particular asset (50A, 50X-50Y) (synchronization) are identified. Additional instructions are inserted (162, 163) to result in a modified synchronization routine with which all computers are updated.

Claims

1. A multiple computer system having at least one application program running simultaneously on a plurality of computers interconnected by a communications network, wherein a like plurality of substantially identical objects are created, each in the corresponding computer and each having a substantially identical name, and said system including a lock means applicable to all said computers wherein any computer wishing to utilize a named object therein acquires an authorizing lock from said lock means which permits said utilization and which prevents all the other computers from utilizing their corresponding named object until said authorizing lock is relinquished.

2. The system as claimed in claim 1 wherein said lock means includes an acquire lock routine and a release lock routine, and both said routines are included in modifications made to said application program running on all said computers.

3. The system as claimed in claim 2 wherein said lock means further includes a shared table listing said named objects in use by any said computer, a lock status for each said object, and a queue of any pending lock acquisitions.

4. The system as claimed in claim 3 wherein said lock means is located within an additional computer not running said application program and connected to said communications network.

5. The system as claimed in claim 2 wherein each said application program is modified before, during, or after loading by inserting a finalization routine to modify each instance at which said application program no longer needs to refer to an object.

6. The system as claimed in claim 3 wherein the application program is modified in accordance with a procedure selected from the group of procedures consisting of re-compilation at loading, pre-compilation prior to loading, compilation prior to loading, just-in-time compilation, and re-compilation after loading and before execution of the relevant portion of application program.

7. The system as claimed in claim 2 wherein said modified application program is transferred to all said computers in accordance with a procedure selected from the group consisting of master/slave transfer, branched transfer and cascaded transfer.

8. A plurality of computers interconnected via a communications link and operating at least one application program simultaneously wherein each said computer in operating said at least one application program utilizes an object only in local memory physically located in each said computer, the contents of the local memory utilized by each said computer is fundamentally similar but not, at each instant, identical, and every one of said computers has an acquire lock routine and a release lock routine which permit utilization of the local object only by one computer and each of the remainder of said plurality of computers is locked out of utilization of their corresponding object.

9. The plurality of computers as claimed in claim 8 wherein the local memory capacity allocated to the or each said application program is substantially identical and the total memory capacity available to the or each said application program is said allocated memory capacity.

10. The plurality of computers as claimed in claim 8 wherein all said distribution update means communicate via said communications link at a data transfer rate which is substantially less than the local memory read rate.

11. The plurality of computers as claimed in claim 8 wherein at least some of said computers are manufactured by different manufacturers and/or have different operating systems.

12. A method of running at least one application program on a plurality of computers simultaneously, said computers being interconnected by means of a communications network, said method comprising the steps of:

(i) creating a like plurality of substantially identical objects each in the corresponding computer and each having a substantially identical name, and

(ii) requiring any of said computers wishing to utilize a named object therein to acquire an authorizing lock which permits said utilization and which prevents all the other computers from utilizing their corresponding named object until said authorizing lock is relinquished.

13. A method as claimed in claim 12 including the further step of:

(iii) providing each said computer with a distributed run time means to communicate between said computers via said communications network.

14. A method as claimed in claim 13 including the further step of:

(iv) providing a shared table accessible by each said distributed run time means and in which is stored the identity of any computer which currently has to access an object, together with the identity of the object.

15. A method as claimed in claim 14 including the further step of:

(v) associating a counter means with said shared table, said counter means storing a count of the number of said computers which seek access to said object.

16. A method as claimed in claim 15 including the further step of:

(vi) providing an additional computer on which said shared program does not run and which hosts said shared table and counter, said additional computer being connected to said communications network.

29. A computer program product comprising a set of program instructions stored in a storage medium and operable to permit a plurality of computers to carry out the method as claimed in claim 12 or 17.

30. A plurality of computers interconnected via a communication network and operable to ensure consistent initialization of an application program running simultaneously of said computers, said computers being programmed to carry out the method as claimed in claim 12 or 17 or being loaded with the computer program product as claimed in claim 29.

17. A method of ensuring consistent synchronization of an application program to be run simultaneously on a plurality of computers interconnected via a communications network, said method comprising the steps of:

(i) scrutinizing said application program at, or prior to, or after loading to detect each program step defining an synchronization routine, and

(ii) modifying said synchronization routine to ensure utilization of an object by only one computer and preventing all the remaining computers from simultaneously utilizing their corresponding objects.

18. The method claimed in claim 17 wherein step (ii) comprises the steps of:

(iii) loading and executing said synchronization routine on one of said computers,

(iv) modifying said synchronization routine by said one computer, and

(v) transferring said modified synchronization routine to each of the remaining computers.

19. The method as claimed in claim 18 wherein said modified synchronization routine is supplied by said one computer direct to each of said remaining computers.

20. The method as claimed in claim 18 wherein said modified synchronization routine is supplied in cascade fashion from said one computer sequentially to each of said remaining computers.

21. The method claimed in claim 17 wherein step (ii) comprises the steps of:

(vi) loading and modifying said synchronization routine on one of said computers,

(vii) said one computer sending said unmodified synchronization routine to each of the remaining computers, and

(viii) each of said remaining computers modifying said synchronization routine after receipt of same.

22. The method claimed in claim 21 wherein said unmodified synchronization routine is supplied by said one computer directly to each of said remaining computers.

23. The method claimed in claim 21 wherein said unmodified synchronization routine is supplied in cascade fashion from said one computer sequentially to each of said remaining computers.

24. The method as claimed in claim 17 including the further step of:

(ix) modifying said application program utilizing a procedure selected from the group of procedures consisting of re-compilation at loading, pre-compilation prior to loading, compilation prior to loading, just-in-time compilation, and re-compilation after loading and before execution of the relevant portion of application program.

25. The method as claimed in claim 17 including the further step of:

(x) transferring the modified application program to all said computers utilizing a procedure selected from the group consisting of master/slave transfer, branched transfer and cascaded transfer.

26. In a multiple thread processing computer operation in which individual threads of a single application program are simultaneously being processed each on a corresponding one of a plurality of computers interconnected via a communications link, and in which objects in local memory physically associated with the computer processing each thread have corresponding objects in the local memory of each other said computer, the improvement comprising permitting only one of said computers to utilize an object and preventing all the remaining computers from simultaneously utilizing their corresponding object.

27. The improvement as claimed in claim 26 wherein an object residing in the memory associated with one said thread and to be utilized has its identity communicated by the computer of said one thread to a shared table accessible by all other said computers.

28. The improvement as claimed in claim 26 wherein an object residing in the memory associated with one said thread and to be utilized has its identity transmitted to the computer associated with another said thread and is transmitted thereby to a shared table accessible by all said other computers.