System and method for profile-based, on-the-fly optimization of library code

• US 6,202,205 B1
• Filed: 07/21/1998
• Issued: 03/13/2001
• Est. Priority Date: 07/21/1998
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: MacRoberts, Patrick F., Saboff, Michael L.
• Primary Examiner(s): Chaki, Kakali
• Application Number:
  US09/120,038
• Time in Patent Office: 966 Days
• Field of Search: 395/701-705, 395/712, 395/710, 395/709, 707/200, 707/201, 707/202, 707/203, 709/300, 709/302, 709/305, 709/310, 709/312, 709/331, 717/1-5, 717/9, 717/10, 717/11
• US Class Current: 717/151
• CPC Class Codes: G06F 8/443 Optimisation

Abstract

A system and method for profiling the execution of a software library used by an application, creating an optimized library based on the profiling, and updating to the optimized library without halting the application. The application is running using an unoptimized version of a replaceable library. The replaceable library is profiled while being used by the application and produces a set of profile data. The profile data, generated by actual execution of the replaceable library on the end-user application, is used to create an optimized version of the library. The application can then update from the unoptimized version of the library to the optimized version of the library. The invention also allows for a system with several applications, each using a different version of an optimized library simultaneously, each optimized version of the library custom optimized for the application using it.

Claims

1. A software system embodied in a computer-readable medium for optimizing a software library during execution while preserving software application program compatibility, the system comprising:

a software application program;

a profiling version of a replaceable software library that provides a service, the profiling version including profiling functionality, the software application using the service;

profile data generated by the profiling functionality in response to use of the profiling version by the software application;

base software comprising one or more software routines that when compiled and linked performs the service;

a code generator to transform the base software responsive to the profile data to form optimized object code; and

a linker for creating an optimized version of the replaceable software library in response to the optimized object code, to provide the same service as the profiling version of the replaceable software library.

2. A software system according to claim 1, the software application including an interface library linked with the software application, the interface library constructed and arranged to provide the only interface between the software application and the replaceable software library.

3. A software system according to claim 2, the system further comprising a registry containing version and location information of the replaceable software library, so as to indicate to the interface library whether to use the profiling version or the optimized version of the replaceable software library.

4. A software system according to claim 3, the registry being a hierarchical registry allowing per process library selection, connecting the application to the correct version of the replaceable software library.

5. A software system according to claim 1, wherein the base software is source code, comprising uncompiled software routines;

and

the code generator comprises an optimizing compiler, the optimizing compiler constructed and arranged for transforming the source code into the optimized object code.

6. A software system according to claim 1, wherein the base software is intermediate code comprising compiled software routines;

and

the code generator comprises an optimizer constructed and arranged to transform the intermediate code into the optimized object code.

7. A method of replacing a software library used by a software application with an optimized software library generated by the profiling the software library, while preserving application program compatibility, the method comprising the steps:

executing a software application, the software application linked to profiling version of a replaceable library, the profiling version of the replaceable library including functionality to profile the replaceable library when the replaceable library is executed;

generating a profile of the replaceable library as the profiling version of the replaceable library is used by the software application;

building an optimized version of the replaceable library based on the profile;

updating the replaceable library used by the application from the profiling version of the replaceable library to the optimized version of the replaceable library without halting execution of the software application.

8. A method according to claim 7, whereby the step of generating the profile is followed by the step of:

updating the replaceable library used by the application to an unoptimized version of the replaceable library without halting execution of the software application, so as to avoid using the inefficient profiling version of the replaceable library while the building step is creating the optimized version of the replaceable library.

9. A method according to claim 7, wherein the step of building an optimized version of the replaceable library comprises the following steps:

generating optimized object code from base software and the profile;

linking the optimized object code to create the optimized version of the replaceable library.

10. A method according to claim 9, wherein the base software is uncompiled source code and the step of generating the optimized object code is performed by compiling the uncompiled source code with an optimizing compiler, the compiler receiving as inputs the uncompiled source code and the profile, the compiler creating optimized object code.

11. A method according to claim 7, wherein the step of updating the replaceable library comprises the following steps:

marking a registry to indicate that the optimized version of the replaceable library is created;

upon the next execution of the replaceable library by the software application, detecting the marking of the registry;

replacing the profiling version of the replaceable library with the optimized version of the replaceable library in response to the detection of the marking of the registry;

continuing execution using the optimized version of the replaceable library.

12. A method of allowing two or more applications to each use a different optimized version of a replaceable software library, each version of the replaceable optimized library optimized based on the execution of the application using the version, the method comprising:

executing a first application using an unoptimized version of a replaceable software library;

executing a second application using the unoptimized version of the replaceable software library;

generating a first optimized version of the replaceable software library, optimized based on the step of executing the first application;

generating a second optimized version of the replaceable software library, optimized based on the step of executing the second application;

updating the replaceable software library used by the first application from the unoptimized version of the replaceable software library to the first optimized version of the replaceable software library;

updating the replaceable software library used by the second application from the unoptimized version of the replaceable software library to the second optimized version of the replaceable software library.

13. A method of revising a profiling version of a replaceable library provided for use by an application with an optimized version of a replaceable library, the method comprising the steps:

providing a profiling version of a replaceable library for use by an application, the profiling version of the replaceable library including functionality to profile the replaceable library when the replaceable library is executed;

generating a profile of the replaceable library as the profiling version of the replaceable library is executed by the software application;

building an optimized version of the replaceable library based on the profile;

providing an optimized version of the replaceable library to the application while the application is still executing;

whereby the steps of generating the profile and building the optimized version of the replaceable library occur while the step of providing the profiling version of the replaceable library is still occurring.

14. A method according to claim 13

where the step of providing the profiling version of the replaceable library is followed by the step:

providing a profiling version of a replaceable library for use by an application, the profiling version of the replaceable library including functionality to profile the replaceable library when the replaceable library is executed;

and whereby the steps of generating the profile and building the optimized version of the replaceable library occur while the step of providing the unoptimized version of the replaceable library is still occurring.