Replication of object graphs

• US 20070126750A1
• Filed: 10/18/2006
• Published: 06/07/2007
• Est. Priority Date: 10/25/2005
• Status: Active Grant

• Current Assignee: Waratek Limited (Waratek Holdings Ltd.)
• Original Assignee: Waratek Pty Limited
• Inventors: Holt, John
• Granted Patent: US 8,015,236 B2
• Time in Patent Office: Days
• US Class Current: 345/587
• 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 updating of only some memory locations in a multiple computer environment in which at least one applications program (50) executes simultaneously on a plurality of computers M1, M2 . . . Mn each of which has a local memory, is disclosed. Objects A and B in each local memory are disclosed which each include primitive fields (11). However, the simultaneous operation of the application program (50) can result in a “non-primitive” reference field (10) in one machine which must then be replicated in all other machines. However, the reference field (10) references another object (H) in the one machine'"'"'s local memory so corresponding objects (T, K) must be created in the local memory of each other machine and be referenced by the corresponding non-primitive field (10).

Claims

1. A method of replicating non-primitive fields of duplicated objects in a multiple computer environment in which different portions of at least one application program execute simultaneously on different ones of multiple computers interconnected via a communications network, said method of comprising the steps of:

(i) creating a concordance table and for each object present in any one of said multiple computers making the entries in said concordance table correspond to each reference to said object,

(ii) replicating said concordance table in each computer or allowing each computer to access a corresponding portion of a single concordance table for all machines present in a server computer, each said entry in said concordance table containing a local pointer to the local memory object referenced by the object of said one machine, and

(iii) having each said other machine designate a corresponding non-primitive field and local object and entering the corresponding local pointer of the corresponding local memory object in said table or tables.

2. The method as claimed in claim 1 including the further step of:

(iv) utilizing a global name in said table(s) corresponding to all local pointers of corresponding non-primitive fields or corresponding objects.

3. The method as claimed in claim 1 including the further step of:

(v) where processing of one of said application program portions dictates the creation of a second or subsequent referenced non-primitive field in one of said machines, creating a corresponding second or subsequent referenced non-primitive field in each of the other ones of said machines.

4. The method as defined in claim 3 including the further steps of:

(vi) executing said different portions of said application program utilizing one of multiple threads within each said computer, and

(vii) having the thread which dictates the creation of said second or subsequent referenced non-primitive field, instruct each of said other ones of said computers to create said corresponding second or subsequent referenced non-primitive field.

5. The method as defined in claim 3 including the further steps of:

(viii) executing said different portions of said application program utilizing one of multiple threads within each said computer, and

(ix) having a different thread from the thread which dictates the creation of said second or subsequent referenced non-primitive field, instruct each of said other ones of said computers to create said corresponding second or subsequent referenced non-primitive field.

11. A plurality of computers interconnected via a communications network and operable to ensure carrying out of the method as claimed in claim 1.

12. 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 claimed in claim 1.

13. A single computer adapted to co-operate with at least one other computer in order to carry out the method as claimed in claim 1 or form the computer system as claimed in claim 6.

6. A multiple computer system in which different portions of at least one application program execute simultaneously on different ones of the multiple computers which are interconnected via a communications network, wherein for each non-primitive field created in any one of said computers there is a corresponding entry in a concordance table accessible by all said computers or replicated in each said computer, said table entry containing a local pointer to the local memory object referenced by said non-primitive field of said one computer, and wherein each other said computer designates a corresponding non-primitive field and local object and the corresponding local pointer of the corresponding local memory object is entered in said concordance table or tables.

7. The system as claimed in claim 6 wherein said table or tables utilize a global name corresponding to all local pointers of corresponding non-primitive fields or corresponding objects.

8. The system as claimed in claim 6 wherein for each second or subsequent referenced non-primitive field in one of said computers, a corresponding second or subsequent referenced non-primitive field is created in each of the other ones of said computers.

9. The system as claimed in claim 8 in which multiple thread processing is utilized in each said computer to execute a different portion of said application program, and the thread which dictates the creation of said second or subsequent referenced non-primitive field, instructs each of the other ones of said computers to create said second or subsequent referenced non-primitive field.

10. The system as claimed in claim 8 in which multiple thread processing is utilized in each said computer to execute a different portion of said application program, and a different thread from the thread which dictates the creation of said second or subsequent referenced non-primitive field, instructs each of the other ones of said computers to create said second or subsequent referenced non-primitive field.