ROM Paging Guide

Describes demand paging when applied to ROM demand paging.

Introduction

Demand paging using ROM demand paging is used when the files to be paged are in the core ROM image and not using another file system such as ROFS.

Background information

The following are useful background information for Demand Paging using ROM demand paging:

  • Demand Paging

  • ROM paging

ROM Demand Paging features

Demand paging (using ROM demand paging) provides the following features compared to code paging and writable data paging :

  • Lower RAM overhead

  • Lower performance overhead.

ROM Demand Paging limitations

The following are known limitations for Demand Paging (using ROM demand paging) compared to the other types of code paging:

  • If the executable has static dependencies, then it is best to place these dependencies in ROFS. This is a limitation of ROFS and not ROM demand paging.

  • This paging system can only be used with files that are stored using the ROM filing system. This is because ROM images using the ROM filing system are designed to be executed in place.