The QNX Neutrino RTOS can run on single-core or multicore systems.
Multiprocessing systems can be in these forms:
- Discrete or traditional
- A system that has separate physical processors hooked up in
multiprocessing mode over a board-level bus.
- Multicore
- A chip that has one physical processor with multiple CPUs
interconnected over a chip-level bus.
Multicore processors deliver greater computing power through concurrency,
offer greater system density, and run at lower clock speeds than
uniprocessor chips.
Multicore processors also reduce thermal dissipation, power consumption, and
board area (and hence the cost of the system).
Multiprocessing includes several operating modes:
- asymmetric, where a separate OS, or a separate instantiation of the same OS,
runs on each CPU.
- symmetric, where a single instantiation of an OS manages all CPUs
simultaneously, and applications can float to any of them.
- bound, where a single instantiation of an OS manages all CPUs
simultaneously, but each application is locked to a specific CPU.
Note:
To determine how many processors there are on your system, look at the
num_cpu entry of the system page.
For more information, see the
System Page
chapter of
Building Embedded Systems.