High latency on supposedly appropriate PC

Hello,

Yes, yet another post on latency issues.
I get really high numbers above 250000 just by starting Firebox or Glxgears.

My Linuxcnc dedicated PC is old but I thought good enough for the task:

Amd Athlon64 X2 4400+ (dual core)
Nvidia 7800 GTX
2Go of RAM

The lscpi -vv listing is attached...



So I have seen a lot of different things/hacks to attempt reducing the latency but before I mess up everything, I'd like to know what is the obvious thing to start with on my computer.

Thanks a lot.

Hi

Rather sounds as though video is the area to probe first

01:00.0 VGA compatible controller: nVidia Corporation G70 [GeForce 7800 GTX] (rev a1)
......
Kernel driver in use: nvidia
Kernel modules: nvidia-173, nvidiafb, nouveau

You have the nvidia proprietary driver from the restricted packages installed (nvidea-173)

The way that nvidia drivers do openGL has been linked to a lot of problems with latency

You can remove nvidea-173 and the card will work with nouveau (the open source driver)

This gives a start, you may have to google further
askubuntu.com/questions/12937/remove-nvi...d-go-back-to-nouveau

See what effect that has first, the next step might be to add isolcpus=1 to the kernel boot line, but one thing at a time so you can be clear what had which effect

regards

Thank that did work very well, now max at 11000 whith to glxgears and youtube playing HD content...
The start of Firefox happens without a spike...

Now the only issue is that this "nouveau" driver seems to do soft OpenGL and Blender will then be very slow...

gaeldk wrote:

Thank that did work very well, now max at 11000 whith to glxgears and youtube playing HD content...
The start of Firefox happens without a spike...

Now the only issue is that this "nouveau" driver seems to do soft OpenGL and Blender will then be very slow...

It doesn't do 3D accelerated thats for sure, but you want a stable low latency machine controller.
It will be fast enough for that

regards