Methods and apparatus for concurrently executing a garbage collection process during execution of a primary application program
View Patent ↗A wireless mobile communication device has an application program and a garbage collection program stored in memory. The garbage collection program is configured to identify a root set of referenced objects of the application program with use of a reference indicator array and to perform a mark and sweep process based on the root set of referenced objects. The reference indicator array has a plurality of reference indicators where each referenced indicator corresponding to a referenced object is set as referenced. The application program is configured to be executed during execution of a mark and sweep process of the garbage collection program, such that information received or provided via the user interface during the execution of the mark and sweep process is received or provided without suspension or delay. The application program has computer instructions which are based on an instruction set defined by a plurality of opcodes or native codes, including a single predefined opcode or a single predefined native code which is a “get object reference” instruction. Each “get object reference” instruction is associated with a target object and is defined to retrieve a reference from the target object and also set one of the reference indicators corresponding to the target object as referenced in the reference indicator array.
1. A wireless mobile communication device, comprising:
one or more processors;
a user interface, coupled to the one or more processors, and comprising at least one of a keyboard or a display;
memory coupled to the one or more processors;
an application program, stored in the memory, and configured to receive or provide information via the user interface;
a garbage collection program, stored in the memory, and configured to identify a root set of referenced objects of the application program with use of a reference indicator array and to perform a mark and sweep process based on the root set of referenced objects, the reference indicator array having a plurality of reference indicators where each referenced indicator corresponding to a referenced object is set as referenced; and
the application program being configured to be executed during execution of the mark and sweep process of the garbage collection program, such that information received or provided via the user interface during the execution of the mark and sweep process is received or provided without suspension or delay, the application program being based on an instruction set comprising a predefined opcode or native code which is defined to: (1) retrieve a reference from a target object, and (2) set one of the reference indicators corresponding to the target object as referenced in the reference indicator array.
2. The wireless mobile communication device of claim 1 , wherein the application program is derived from a JAVA application program.
3. The wireless mobile communication device of claim 1 , comprising a handheld telephony device operative in a wireless communication network.
4. The wireless mobile communication device of claim 1 , wherein the predefined opcode or native code is a single predefined opcode of the one or more processors.
5. The wireless mobile communication device of claim 1 , wherein the predefined opcode or native code is a single predefined native code.
6. The wireless mobile communication device of claim 1 , wherein the predefined opcode or native code comprises a GETREF instruction.
7. The wireless mobile communication device of claim 1 , wherein the predefined opcode or native code comprises an AALOAD instruction.
8. The wireless mobile communication device of claim 1 , wherein the predefined opcode or native code is further defined to set the reference indicator in the reference indicator array as referenced for the target object if the mark and sweep process is currently being executed, and to refrain from setting the reference indicator in the reference indicator array as referenced for the target object if the mark and sweep process is not currently being executed.
9. The wireless mobile communication device of claim 1 , wherein the mark and sweep process is further configured to, for each referenced object having one of the reference indicators set as referenced in the reference indicator array: (1) set a marked indicator in a marked indicator array as marked for the referenced object, (2) examine a content of the referenced object for a further referenced object, and (3) set one of the reference indicators corresponding to said further referenced object as referenced in the reference indicator array.
10. The wireless mobile communication device of claim 1 , wherein the mark and sweep process is further configured to, for each referenced object having one of the reference indicators set as referenced in the reference indicator array, (1) set a marked indicator in a marked indicator array as marked for the referenced object, (2) examine a content of the referenced object for a further referenced object, and (3) set one of the reference indicators corresponding to said further referenced object as referenced in the reference indicator array, the garbage collection program being further configured to:
free objects identified as garbage in order to reclaim memory space in memory, the objects identified as garbage being those that fail to have a corresponding one of the marked indicators set as marked in the marked indicator array; and
consolidate referenced objects such that available contiguous memory space in the memory is increased.
11. A wireless mobile communication device, comprising:
one or more processors;
a user interface, coupled to the one or more processors, and comprising at least one of a keyboard or a display;
memory coupled to the one or more processors;
an application program, stored in the memory, and configured to receive or provide information via the user interface;
a garbage collection program stored in the memory;
the garbage collection program being configured to identify a root set of referenced objects of the application program with use of a reference indicator array and to perform a mark and sweep process based on the root set of referenced objects, the reference indicator array having a plurality of reference indicators where each referenced indicator corresponding to a referenced object is set as referenced; and
the application program being configured to be executed during execution of the mark and sweep process of the garbage collection program, such that information received or provided via the user interface during the execution of the mark and sweep process is received or provided without suspension or delay, the application program being based on an instruction set comprising a predefined opcode or native code which is defined to: (1) create a new object for the application program, (2) set one of the reference indicators corresponding to the new object as referenced in the reference indicator array, and (3) set one of the marked indicator corresponding to the new object as marked in the marked indicator array.
12. The wireless mobile communication device of claim 11 , wherein the application program is derived from a JAVA application program.
13. The wireless mobile communication device of claim 11 , comprising a handheld telephony device operative in a wireless communication network.
14. The wireless mobile communication device of claim 11 , wherein the predefined opcode or native code is a single predefined opcode of the one or more processors.
15. The wireless mobile communication device of claim 11 , wherein the predefined opcode or native code is a single predefined native code.
16. The wireless mobile communication device of claim 11 , wherein the predefined opcode or native code is a CREATE instruction.
17. The wireless mobile communication device of claim 11 , wherein the predefined opcode or native code is a NEW instruction.
18. The wireless mobile communication device of claim 11 , wherein the predefined opcode or native code is further defined to set the reference indicator in the reference indicator array as referenced for the target object if the mark and sweep process is currently being executed, and to refrain from setting the reference indicator in the reference indicator array as referenced for the target object if the mark and sweep process is not currently being executed.
19. The wireless mobile communication device of claim 11 , wherein the mark and sweep process is further configured to, for each referenced object having one of the reference indicators set as referenced in the reference indicator array: (1) set a marked indicator in a marked indicator array as marked for the referenced object, (2) examine a content of the referenced object for a further referenced object, and (3) set one of the reference indicators corresponding to said further referenced object as referenced in the reference indicator array.
20. The wireless mobile communication device of claim 11 , wherein the mark and sweep process is configured to, for each referenced object having one of the reference indicators set as referenced in the reference indicator array, (1) set a marked indicator in a marked indicator array as marked for the referenced object, (2) examine a content of the referenced object for a further referenced object, and (3) set one of the reference indicators corresponding to said further referenced object as referenced in the reference indicator array, the garbage collection program being further configured to:
free objects identified as garbage in order to reclaim memory space in memory, the objects identified as garbage being those that fail to have a corresponding one of the marked indicators set as marked in the marked indicator array; and
consolidate referenced objects such that available ontiguous memory space in the memory is increased.