From: eLinux.org

Parallel RC Scripts

Contents

• 1 Description
• 2 How to implement or use
• 3 Expected Improvement
• 4 Resources
  • 4.1 Projects
• 5 Specifications
• 6 Patches
• 7 Case Studies
  • 7.1 Case 1
  • 7.2 Case 2
  • 7.3 Case 3

Description

One way to reduce bootup time is to run RC scripts in parallel. RC scripts are normally run in sequence in a desktop configuration of Linux. By running the scripts in parallel, it is possible to take advantage of the multi-processing capabilities of the OS (such as overlapping execution with I/O, etc.)

How to implement or use

See the projects listed below for details on different methods of doing this.

Expected Improvement

[Not determined yet.]

Resources

Projects

• InitNG: a new replacement for SysV init. Boots your system much faster by running as much as possible asynchronously. See InitNG
• IBM article on on using Makefile techniques to express dependencies between services and support parallel service start. See BootFaster
• Richard Gooch project to rewrite boot script system from scratch. Eliminates lots of BSD and SYS V-isms, and introduces dependencies. See boot scripts
• Serel project - for parallelizing service startup. Commands are inserted into RC scripts to cause needed services to start (based on XML database of dependencies). See fastboot

Specifications

• LSB specification for comments in RC Scripts which allow parallization. See [1]

Patches

None.

Case Studies

[None yet.]

Case 1

[put information about an actual use of this technique here. A case study should include:]

Hardware:: [hardware description here] Kernel Version:: [kernel version here] Configuration:: [information about the configuration used here] Time without change:: [put that here] Time with change:: [put that here]

[Add any additional notes as you see fit.]

Case 2

Case 3

Category:

• HOWTOs