Installing LinuxCNC On HP T610 Thin Client

Joco's latency script was run with no base thread

For completeness here is the servo only latency-histogram - as can be seen very little difference to Joco's script and base thread 

Thanks James - I tried the idle=poll method and have a servo around 193.
Ran the hog.sh script and i get the following in the terminal window -
pid 3745's current affinity mask: 1
taskset: failed to set pid 3745's affinity: Invalid argument

 

Why the 250us servo thread ?

I honestly think that if you had the same OS kernel and desk top environment you’d be getting the same or at least similar results.

The choice of desktop environment can affect latency due to the differing resources each consumes.
Gnome is on the heavier side where as xfce is one of the lighter ones.
When I did my respin of Mint I went for the xfce version as a base rather Mate. I tried a few kernels and decide on 4.19.106  as that gave better results than the 5 series available at the time. 
Sometimes, probably more so on the lighter machines, the latest distro and kernel isn’t the best option.

In the case of this machine i suspect your issue is kernel/distro related.  When i did my initial work i tried debian 10 and ended up on mint 19.3 for a very good reason.

i have not done any tests on Debian 11(bullseye).  I am not surprised it performs poorly. If you are serious about needing bullseye then you might need to look at custom kernel compiles.  

Thanks all

The main reason I've gone with Bullseye is so I can run qtpyvcp with python 3.

Sound like time to give up on the t610

I don't think that would have been the best of ideas considering the specs of the little machine. Might have been a little too heavy for it.

I wouldn't be too quick to dismiss the T610.  I have Arch linux running on it with similar latency to my Mint 19.3 tests.  And when it comes to "modern" or "latest and greatest" not much is going to beat Arch.

Cheers - J.

I was more thinking of the use qtpyvcp. The figures so far look like it should be good for Axis.

I'd be interested in giving Buster a go as well, with a 4.19.xxx kernel.

I have one that I'm waiting for delivery of.

I also have a T5135 that I have win98 on that I use for my Needham programmer.

Arch isn't really for those that are going to throw their hands up in the air.

A couple of years ago I had Linuxcnc running with Linux From Scratch.....yeah I really had some time on my hands.

its fine with Axis.  It's actually  fine with qtpyvcp. The "killer" is VTK which is a bit of a cpu hog. But I'm going to do some more tests of that particular component now I have working monokrom-plasma sim.

I don't mind putting some work in to get a decent lathe setup - but I'm a machinist 1st and computer boffin 20th! 

My current lathe is actually running a parallel port setup with pathpilot. I have to say having used pathpilot for a few years it is perfect for what I need and the conversational programming side of it is the best I have used. I'm now building a new lathe which will have some extra features, external controls, toolchanger etc. Unfortunately so much of the path pilot GUI has been custom coded in Python it is hard to find your way through it and even the simplest mods can take some work. Probe-basic-lathe looks good - but you need a high screen resolution/17" monitor to make it workable and I want to use a 15" touchscreen (like on pathpilot) which will be built into a panel with a small PC in the back.

Hence I was going to have a go at building my own screens in QTPYVCP and then use the Pathpilot python conversational code reworked as a basis for conversational programming. That might be a big dream but at the moment looks to be the only way to get what I want.