About This Guide

Optimizing Startup Times describes strategies and techniques that you can use to reduce the time between when you power on and when Screen is ready on your system. Because the time to boot is dependent upon the design and implementation of your system, this guide describes general techniques instead of concrete steps to optimize your system.

Screen supports systems with or without displays, and systems with or without a GPU. For these systems, optimization opportunities are mostly in the areas of starting up your base system (IPL, kernel, Core OS) and Screen. There are more optimization techniques for your applications if your system supports graphics and displays. This guide describes many different possible optimization techniques. Use the techniques that are applicable to your system.

In this document, we refer to:
  • content as a static image or a video
  • splash screen application (or splash_screen_application in the examples) as the program, which you create to show content on the display. A splash screen application can use both the GPU and displays that are supported by your system. Typically, for an optimized startup time, we recommend that splash screen applications avoid using the GPU.
Note: It's important to note that the actual time saved (typically in the order of milliseconds) varies between hardware platforms. As the system architect or developer, you should implement the optimization techniques that meet the requirements for your system.

Some hardware platforms aren't functional until all the necessary device drivers are started. For those platforms, you won't be able to take advantage of all the techniques described in this guide to optimize the startup time. Some of the techniques described in this guide are targeted for hardware platforms that permit you to start device drivers as required, rather than requiring that all device drivers be started before any applications can run.

We recommend that you review the following guides to have a good understanding of how to design an embedded system to boot quickly and work with multiple OS images (such as creating a primary and secondary IFS): Here's what's contained in this guide:
For information on: Go to:
An overview of the areas you can optimize In addition, an overview of the Screen optimization strategy is provided Optimizing Screen Startup Time
A summary of the techniques to split the IFS into a primary and secondary IFS Configure a Primary and Secondary IFS on the System
A summary of the techniques to optimize the Screen configuration file Optimize the Screen Configuration File
A summary of techniques to optimize your boot script Optimize the Boot Script
A summary of techniques and strategies to optimize the implementation of your splash screen application Optimize the Splash Screen Application
A summary of techniques you can use to optimize the boot time of an embedded system Other System Optimization Practices