Memory management in BlackBerry PlayBook OS

By design, the BlackBerry PlayBook OS architecture helps ensure that faults, including memory errors, are confined to the program that caused them. Programs are less likely to cause a cascade of faults because processes are isolated from each other and from the microkernel. Even device drivers behave like regular debuggable processes:

Diagram showing the microkernel architecture.

This robust architecture ensures that crashing one program has little or no effect on other programs throughout the system. If a program faults, you can be sure that the error is restricted to that process's operation.

The full memory protection means that almost all the memory addresses your program encounters are virtual addresses. The process manager maps your program's virtual memory addresses to the actual physical memory; memory that is contiguous in your program may be transparently split up in your system's physical memory:

Diagram showing how the process manager allocates memory into pages.

The process manager allocates memory in small pages (typically 4 KB each). To determine the size for your system, use the sysconf function.