Systems and methods for cache and pool initialization on demand

• US 7,756,910 B2
• Filed: 10/15/2004
• Issued: 07/13/2010
• Est. Priority Date: 05/21/2004
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: BEA Systems Incorporated (Oracle Corporation)
• Inventors: Chow, Thorick, White, Seth
• Primary Examiner(s): Alam; Hosain T
• Assistant Examiner(s): OBERLY, VAN HONG
• Application Number:
  US10/967,674
• Publication Number:
  US 20050262305A1
• Time in Patent Office: 2,097 Days
• Field of Search: 707/103.Y, 711/118
• US Class Current: 707/813
• CPC Class Codes: G06F 12/023 Free address space management
• CPC Class Codes: G06F 12/0891 using clearing, invalidating or resetting means

Abstract

Users and processes are provided with various features to control the memory usage by a cache and pool dynamically at runtime. The cache and pool can be initialized on demand to remove idle objects of classes from them without the server being restarted. When the cache and pool reach their maximum sizes, idle objects in them may be removed to make room for newly active objects using various strategies in batches, where the schedule (periodicity), size and processing time of each batch can be dynamically adjusted. When a newly created object is being added to a full cache where each object is enrolled in a transaction, one or more active objects may be passivated from the cache based on various criteria to make room for the new instance to be added. Various features of the cache and pool can be defined in a configuration file.

Claims

1. A system to support cache initialization on demand, comprising:

a container, associated with a transaction, to hold objects of one or more classes defined by an object-oriented programming language, wherein the container is a part of an application server;

a cache, within the container, to store in a first memory a first one or more objects of the one or more classes, wherein the first one or more objects stored in the cache can be at least one of enrolled in the transaction and idle;

a pool, within the container, to store in a second memory a second one or more objects of the one or more classes wherein the second one or more objects stored in the pool are initiated and idle with a readiness level lower than the first one or more objects stored in the cache;

an on-demand initialization process associated with a console for triggering the initialization of the cache of the class; and

wherein the container operates to;

initialize the cache on demand at runtime before a class in the one or more classes is deployed, by removing one or more idle objects of the class from the cache to the pool; and

add at least one said object to the cache, if the at least one said object is already in the pool but not in the cache, when the at least one said object of the one or more classes is enrolled in the transaction.

2. The system according to claim 1, wherein:

the class is one of an interface, a module, and a software object.

3. The system according to claim 1, wherein:

the container is further capable of initializing the cache without shutting down and/or starting up an application server running the cache.

4. The system according to claim 1, wherein:

the container is further capable of performing at least one of;

setting idle time of the at least one said object to zero; and

monitoring the at least one said object.

5. The system according to claim 1, further comprising:

a garbage collector to receive, from the pool, one or more idle objects.

6. The system according to claim 1, wherein:

the container contains a batch scheduler to remove idled objects in batches and set a limit on processing time of each batch based on a feedback from a previous batch.

7. The system according to claim 1, wherein:

the cache and the pool is dedicated to caching objects of a specific type of class.

8. The system according to claim 1, wherein:

only the first one or more objects stored in the cache are ready to be enrolled in a transaction.

9. The system according to claim 1, wherein:

the container can further passivate at least one existing object of the first one or more objects stored in the cache in order to free up space to insert a new object in the cache, when all of the first one or more objects are enrolled in a transaction, wherein the at least one existing object is removed from the cache when a per-instance application code method marks the at least one existing object as a preferred candidate for passivation.

10. The system according to claim 1, wherein:

the container uses a cache control component to remove one or more idle objects of the class from the cache to the pool.

11. The system according to claim 1, wherein:

the container uses a pool control component to remove one or more idle objects of the class from the pool when one or more criteria are met.

12. The system according to claim 1, wherein:

the container operates to initiate the at least one said object if the at least one said object is not already in the cache and the pool, when at least one said object of the one or more classes is enrolled in the transaction.

13. A method to support cache initialization on demand, comprising:

holding objects of one or more classes defined by an object-oriented programming language in a container, wherein the container is associated with a transaction and is a part of an application server;

storing in a first memory a first one or more objects of the one or more classes via a cache in the container, wherein the first one or more objects stored in the cache can be at least one of enrolled in the transaction and idle;

storing in a second memory a second one or more objects of the one or more classes via a pool in the container, wherein the second one or more objects stored in the pool are initiated and idle with a readiness level lower than the first one or more objects stored in the cache;

triggering the initialization process, wherein the on-demand initialization process is associated with a console;

initializing, via the container, the cache on demand at runtime before a class in the one or more classes is deployed, by removing one or more idle objects of the class from the cache to the pool; and

adding, via the container, at least one said object to the cache, if the at least one said object is already in the pool but not in the cache, when the at least one said object of the one or more classes is enrolled in the transaction.

14. The method according to claim 13, further comprising:

initializing the cache without shutting down and/or starting up an application server running the cache.

15. The method according to claim 13, further comprising:

performing at least one of;

setting idle time of the at least one said object to zero; and

monitoring the at least one said object.

16. A machine readable storage medium having instructions stored thereon that when executed by a processor cause a system to:

hold objects of one or more classes defined by an object-oriented programming language in a container, wherein the container is associated with a transaction and is a part of an application server;

store a first memory a first one or more objects of the one or more classes via a cache in the container, wherein the first one or more objects stored in the cache can be at least one of enrolled in the transaction and idle;

store in a second memory a second one or more objects of the one or more classes via a pool in the container, wherein the second one or more objects stored in the pool are initiated and idle with a readiness level lower than the first one or more objects stored in the cache;

trigger the initialization of the cache of the class via an on-demand initialization process, wherein the on-demand initialization process is associated with a console;

initialize, via the container, the cache on demand at runtime before a class in the one or more classes is deployed, by removing one or more idle objects of the class from the cache to the pool; and

add, via the container, at least one said object to the cache, if the at least one said object is already in the pool but not in the cache, when the at least one said object of the one or more classes is enrolled in the transaction.

17. The machine readable medium of claim 16, further comprising instructions that when executed cause the system to:

initialize the cache without shutting down and/or starting up an application server running the cache.

18. The machine readable medium of claim 16, further comprising instructions that when executed cause the system to:

perform at least one of;

setting idle time of the at least one said object to zero; and

monitoring the at least one said object.

19. A system to support cache initialization on demand, comprising:

means for holding objects of one or more classes defined by an object-oriented programming language in a container, wherein the container is associated with a transaction and is a part of an application server;

means for storing in a first memory a first one or more objects of the one or more classes via a cache in the container, wherein the first one or more objects stored in the cache can be at least one of enrolled in the transaction and idle;

means for storing in a second memory a second one or more objects of the one or more classes via a pool in the container, wherein the second one or more objects stored in the pool are initiated and idle with a readiness level lower than the first one or more objects stored in the cache;

means for triggering the initialization of the cache of the class via an on-demand initialization process, wherein the on-demand initialization process is associated with a console;

means for initializing via the container, the cache on demand at runtime before a class in the one or more classes is deployed, by removing one or more idle objects of the class from the cache to the pool; and

means for adding, via the container, at least one said object to the cache, if the at least one said object is already in the pool but not in the cache, when the at least one said object of the one or more classes is enrolled in the transaction.