Which is better RTOS - QNX or VxWorks (:-)


Just starting this thread, to get the more understanding between the QNX and VxWorks.


The figure out which is better, you first need a set of requirement to compare them against. What are you requirement?

What I have heard though is that people that have worked with both seems to prefer QNX when it comes to the OS, but VxWorks when it comes to the development environment. But I guess with the new IDE based on Eclipse ( which VxWorks is using as well ) QNX IDE is definitely gaining grounds.

let’s talk in the following terms,

  1. Memory footprint
  2. Scheduling Algorithms : Flexibility to choose on process basis
  3. Timeslice granularity : Flexibility to define on Process basis if possible
  4. IPC methods efficiency and overhead

Talk to your QNX rep, they have a document ( apparently wrote by a third party ) that compares QNX6 / VxWorks / WinCE.

Is this available somewhere on net also!!

Not that I know of.

Look at:


Well my two cents worth
QNX is a memory protected micro kernel OS, which means your programs run in their own memory space chances of one stamping on another’s memory is zero.
VxWorx does not segregate kernel and user memory space, thereby providing the fastest communication between applications and kernel but there is still a danger of memory corruption.