Delayed unloading of a dynamically loadable file

• US 6,308,184 B1
• Filed: 04/09/1999
• Issued: 10/23/2001
• Est. Priority Date: 04/09/1999
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Hewitt, James A.
• Primary Examiner(s): Alam, Hosain T.
• Assistant Examiner(s): Colbert, Ella
• Application Number:
  US09/288,942
• Time in Patent Office: 928 Days
• Field of Search: 707/1, 707/5, 707/10, 707/100-104, 707/200-206, 711/11, 710/68, 710/200, 714/8, 714/4, 713/321, 709/250, 709/227, 709/239
• US Class Current: 1/1
• CPC Class Codes: G06F 9/4411 Configuring for operating with peripheral devices; Loading of device drivers
• CPC Class Codes: G06F 9/44521 Dynamic linking or loading; Link editing at or after load time, e.g. Java class loading
• CPC Class Codes: G06F 9/44594 Unloading
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99935 Query augmenting and refining, e.g. inexact access
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99956 File allocation

Abstract

A dynamically loadable file, such as a dynamically loadable device driver or library, is delayed from being unloaded from memory for improved memory management and processing operations including reduced unload/load cycles. Prior to terminating execution of select functions, a dynamically loadable driver spawns a delay process that loads the driver and keeps it loaded for a period of time beyond that which it would normally be loaded. Thus, even after a calling process unloads the driver, it remains loaded for a period of time longer because of the spawned delay process and allows the operating system or an application/process to use the driver again within the delay time without requiring the driver to be re-copied into memory or reinitialized. The delay process safely increments the operating system reference count for the driver to keep the driver loaded and then monitors a delay time to subsequently unload the driver.

Claims

1. A method of managing a dynamically loadable file, comprising:

(a) initiating a dynamic load of the file by a first process;

(b) initiating a dynamic unload of the file by the first process; and

,

(c) delaying a removal of the file from a memory in which the file executes, the delaying occurring as a result of the file being loaded by the first process, and wherein delaying the removal includes spawning a second process that initiates a dynamic load of the file.

2. The method of claim 1 wherein the dynamically loadable file is a device driver.

3. The method of claim 2 wherein the device driver is for an imaging device.

4. The method of claim 1 wherein the dynamic load initiated by the second process includes incrementing a reference count for the file.

5. The method of claim 1 wherein the second process that initiates the dynamic load keeps the file loaded for a period of time that extends beyond the initiating of the dynamic unload by the first process.

6. A method of managing a dynamically loadable file, comprising:

(a) initiating a dynamic load of the file by a first process by incrementing a reference count for the file;

(b) initiating a dynamic unload of the file by the first process by decrementing a reference count for the file; and

,

(c) delaying a removal of the file from a memory in which the file executes, the delaying occurring as a result of the file being loaded by the first process.

7. A computer-readable medium having computer-executable instructions for performing steps including:

(a) initiating a dynamic load of a file by a first process;

(b) initiating a dynamic unload of the file by the first process; and

,

(c) delaying a removal of the file from a memory in which the file executes, the delaying occurring as a result of the file being loaded by the first process, and wherein delaying the removal includes spawning a second process that initiates a dynamic load of the file.

8. A method of managing a dynamically loadable file, comprising:

(a) dynamically loading the file in response to a request by a first process;

(b) spawning a second process based on the loading of the file by the first process;

(c) dynamically loading the file in response to a request by the second process;

(d) dynamically unloading the file in response to a request by the first process, but wherein the file remains usable in memory; and

,

(e) dynamically unloading the file in response to a request by the second process after the unloading of the file by the first process.

9. The method of claim 8 wherein the dynamically loadable file is a device driver.

10. The method of claim 9 wherein the device driver is for an imaging device.

11. A computer-readable medium having computer-executable instructions for performing steps including:

(a) dynamically loading a file in response to a request by a first process;

(b) spawning a second process based on the loading of the file by the first process;

(c) dynamically loading the file in response to a request by the second process;

(d) dynamically unloading the file in response to a request by the first process, but wherein the file remains usable in memory; and

,

(e) dynamically unloading the file in response to a request by the second process after the unloading of the file by the first process.