linuxcnc on 64bit OS

grandixximo wrote:

ArcEye wrote:

PS

If you are running a real machine on rt_preempt, don't be tempted to install proprietary video drivers, just because you want to use it for CAD too.

This machine has a 2GB GPU Nvidia card, which works perfectly using the opensource nouveau drivers.

If I build the nvidia drivers via DKMS, I will get a RTAI error every time realtime starts

What gpu are you using?
I won't built proprietary drivers, but if it can improve cad performance with the open source drivers, without rtai error, that would be awesomeness, what GPU is it?
I tried a bunch of gpu with old Ubuntu 10.04 live CD installation, but I never could find a suitable one.

The rt-preempt is more forgiving?
I can install any GPU?
Nvidia or ati?

This machine is just for development, not controlling a cnc machine.
The card was bought for gaming ( its a GT650 I think ), quite honestly for CAD a normal video chip is fine unless you are doing a lot of 3D modelling or something like that.

I don't really know about other cards with rt-preempt, so would be hesitant to recommend anything, but it certainly will not be more forgiving, you are skating along the edge of
acceptable performance with rt-preempt and anything like that can push it over that edge.

regards

I don't really know about other cards with rt-preempt, so would be hesitant to recommend anything, but it certainly will not be more forgiving, you are skating along the edge of
acceptable performance with rt-preempt and anything like that can push it over that edge.

Well... if you are using decent modern hardware, Preemt-RT performance can be quite good:

freeby.mesanet.com/h97-g3258-preemt-rt.png

Note this is using built in (in CPU) Intel Graphics I have not needed nor used a GPU in a long time

Thank you guys for all your help,
Unfortunatly Draftsight does not open up in wheezy
GLIBC_2.15 required, i installed it according to this forum.mepiscommunity.org/viewtopic.php?f=88&t=37022

but the preformance are very very sloppy with the insternal graphics

Mouse movements are late, haven't installed rt kernel yet.

On ubuntu 14.04 CAD performance on same machine are pretty good...

I'm going to try Jessie, see if CAD performance are good on it, if they are i guess i'll wait for the official rt kernel, any idea when that will be available?

I'll wait for the official rt kernel, any idea when that will be available?

Machinekit have been pestering a guy called Nick at Debian to provide an official package for Jessie.

Sounds like it will happen, but when......?

I think preemt-rt 4.0.4-rt1 has just been added to the debian repositories

www.spinics.net/lists/linux-rt-users/msg13416.html

note, I found 4.04.rt1 to have quite poor latency relative to 3.18.13-rt10
(the latest previous preemt-rt kernel), at least on one test machine
so it may take a while for the 4.xx branch to stabilize

Thanks for that

Would have taken a while for that list post to permeate out into the search engines.

I am on 3.18.13-rt10 at present, so will stick with it until I hear better reports.

Looks like 4.xx will be the starting point, so no 3.8.xx rt kernels in packages though?

regards

Draftsight does not seem to agree with Debian Jessie either

I guess i'm back to Ubuntu 14.04

You guys think the debian preempt kernel will work on ubuntu?

packages.debian.org/wheezy/linux-image-rt-amd64

this one?

Ubuntu 14 comes with kernel 3.16 i think, this is 3.2 can it work?

I'll try and report back, if that won't work, any other already built kernels i can use?

You guys think the debian preempt kernel will work on ubuntu?

Possible, but perhaps unlikely

It is quite trivial to build a rt-prempt kernel compared to rtai plus realtime

PCW even posted links to instruction scripts here
www.linuxcnc.org/index.php/english/forum...l-h81?start=20#58548

Just install the package build-essential and give it a go

(you will need to go into make menuconfig and change the first option to 64 bit on the config, but other than that you can leave it as it is)

regards

Thank you so much!

I will try to build my own preempt kernel

BTW i did not try the debian kernel, but i have been sucessfull with the kernel provided here

bitbucket.org/thismaechler/ubuntustudio-14.04-realtimeaudio/

3.18.7-rt1

i'm seeing decent latency with latency-test around 20000, which is better than what i expected, and Linuxcnc is not sending the RTAI error with

SERVO_PERIOD = 75000

which, i think is decent enough, not for stepping, but good enough to run with a Mesa card

I will try to build a fresher kernel see how things go, i am quite happy with the results i see so far, thank you so much for all your help