Performance difference of 6.2.1 and 6.4.1

Comparing versions 6.2.1 and 6.4.1 of QNX Neutrino on the same machine, I found that if I open more than one app on a desktop and manipulate the windows, 6.2.1 remains snappy while 6.4.1 becomes dog slow and uses nearly twice as much memory.

Is the difference in performance due to changes in the OS or Photon?

Maybe it`s a graphics driver issue?

I remember when I first installed 6.4 a while ago the hardware cursor wasn’t enabled by default. Made it really slow on VMware.

Well, I tried the available driver options and display options in 6.4.1. I saw some small variation is resource demand, but the large difference from 6.2.1 remains. Also made sure I was using the hardware cursor.

I’d grab a kernel trace while doing this on both systems. Just run tracelogger while doing your test.

“tracelogger -s5 -n0 -S5M -M -f/dev/shmem/graphics-trace.kev &”

One change is in 6.4 is QNX is running Photon on top of the AG drivers, so there could be a performance hit.


can you elaborate what you mean by "running Photon on top of the AG drivers"?   


If you look on your stock 6.4 system you’ll see you are running io-graphics (Photon) and io-display (GF/AG TDK) at the same time. Basically what is really happening is io-graphics is now just a GF application. You have to be running io-display to run io-graphics, since io-graphics will now open a GF surface and do all it’s rendering there.

Thank you for the reply. Now if I may ask, can you tell me what GF and AG stand for. I get that this is a new layer, so there is probably some advantage to having it, something I’d like to know more about. Sorry if I’m hijacking the thread.

AG and GF are the same. AG (Advance Graphics) TDK is the name QNX gave to the package. … phics.html

However the core of the AG TDK is the GF (Graphics Framework) library. So all the calls start gf_* and it always refers to the GF API so some people refer to it as GF. … -base.html

It sounds like it will allow a user to partition a screen into different areas, one more more of which can run OpenGL 2D or 3D graphics while the other areas are just running plain old Photon applications. This sounds pretty neet. All the OpenGL I’ve seen before on QNX (Quake III I think) took over the entire screen, rather than running in a window.