Method and system for caching managed code for efficient execution on resource-constrained devices

• US 20060190932A1
• Filed: 02/22/2005
• Published: 08/24/2006
• Est. Priority Date: 02/22/2005
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Gilbert, Mark E.
• Granted Patent: US 7,506,310 B2
• Time in Patent Office: Days
• US Class Current: 717/140
• CPC Class Codes: G06F 8/4434 Reducing the memory space required by the program code

Abstract

Described is a system and method that separates a managed code runtime library or program into four parts, comprising a header, resources, metadata and method implementations. The metadata and some or all of the resources are maintained in system memory (RAM) the entire time that the program is running. The method implementations and any non-maintained resources are loaded on demand, and then discarded such as via garbage collection. The amount of memory consumed by a managed code program is thus reduced relative to non-separated environments, but because the metadata and selected resources are in memory, the program execution is highly efficient due to significantly reduced access of data in non-volatile storage. The parts of the assembly that are maintained in RAM can be saved as code library files, providing shared use by programs and efficient loading by eliminating any need to again parse a program to identify the separate parts.

Claims

1. In a computing device, a method comprising:

loading from a storage at least one section of a managed code program into memory;

maintaining at least one section in the memory such that the selected section or sections are not removed in ordinary operation while running the managed code program; and

loading at least some code and/or data of the managed code program into memory on demand.

2. The method of claim 1 wherein maintaining at least one section in the memory comprises caching metadata, the metadata comprising function and variable names, and type information.

3. The method of claim 1 wherein maintaining at least one section in the memory comprises maintaining at least a subset of program resources.

4. The method of claim 3 wherein maintaining at least a subset of program resources comprises keeping string data.

5. The method of claim 3 wherein maintaining at least a subset of program resources comprises keeping user interface-related data.

6. The method of claim 5 wherein loading at least some code and/or data of the managed code program into memory on demand comprises loading other resource data that is not part of the subset.

7. The method of claim 6 wherein loading at least some code and/or data of the managed code program into memory on demand comprises loading image data.

8. The method of claim 5 wherein loading at least some code and/or data of the managed code program into memory on demand comprises loading method code on demand.

9. The method of claim 8 further comprising, maintaining a separate cache in memory for compiled method code.

10. At least one computer-readable medium having computer-executable instructions, which when executed perform the method of claim 1.

11. In a computing device, a system comprising:

a storage that contains managed code programs;

a memory; and

a loader mechanism coupled to the storage to load a managed code program into the memory, the loader mechanism differentiating at least one selected section of the managed code program from at least one other section, such that the selected section and/or sections are loaded into memory and not removed in ordinary operation while running the managed code program.

12. The system of claim 11 wherein a selected section includes metadata comprising function and variable names, and type information.

13. The system of claim 11 wherein a selected section includes at least a subset of program resources.

15. The system of claim 11 wherein the loader mechanism loads other data and/or code of the program on demand, and wherein the other data and/or code include at least one item of a set, the set containing method code and at least a subset of program resources.

16. The system of claim 11 wherein the memory contains a compiled method cache, and wherein a needed method that is not in the compiled method cache is loaded on demand and compiled.

14. The system of claim 14 wherein the subset of program resources comprises at least one item of a set, the set containing strings and other user interface elements.

17. At least one computer-readable medium having computer-executable instructions, which when executed perform steps, comprising:

receiving a request to execute a managed code program;

loading at least one selected section of the managed code program from a storage into memory, including loading program metadata such that the selected data are not removed in ordinary operation while executing the managed code program;

loading at least one other section of the managed code program on demand, including loading a method implementation when needed for managed code program execution.

18. The computer-readable medium of claim 17 wherein loading at least one selected section of the managed code program from the storage into memory comprises loading at least a subset of program resources into the memory, and wherein loading at least one other section of the managed code program on demand comprises loading a resource into the memory on demand.

19. The computer-readable medium of claim 17 wherein loading at least one other section of the managed code program on demand comprises determining that a compiled method corresponding to the method implementation is not compiled in a cache of previously-compiled methods.

20. The computer-readable medium of claim 17 having further computer-executable instructions comprising, saving to a file in storage data in the memory that corresponds to the selected section or selected sections.