RTPREEMPT vs RTAI

BeagleBrainz wrote:

Ok have a MATE desktop version with 2.9 uploading. Very very slow upload speeds here at the moment.
It’s about 2300 here now expect the link put up sometime around 0500 my time. Not gunna stay up all night this time

Oh man this is awesome! Thank you so much! Definitely saves me a ton of head scratching lol.

-Greg

Did the install. Everything seems to have gone well (havent launched LinuxCNC yet though).

I had some questions:

1. Should I do the update to 19.3 Tricia?
2. The update manager shows a lot of updates, wondering if I should do them? One of them is a Kernel update...
3. The latency is hovering between 50000 and 75000 ns. With the RTAI build I was using, I was seeing sub 8000 pretty consistently. Remember I am using the PCIe (6i25) mesa card. Am I going to be OK, or should I be using RTAI?

Thanks,
Greg

bbsr_5a wrote:

latency below 1000k is good to go

That is also not correct, 200k to 300k can work but not always as they might have excursions that surpass that.

BeagleBrainz wrote:

snowgoer540 wrote:

Did the install. Everything seems to have gone well (havent launched LinuxCNC yet though).

I had some questions:

1. Should I do the update to 19.3 Tricia?
2. The update manager shows a lot of updates, wondering if I should do them? One of them is a Kernel update...
3. The latency is hovering between 50000 and 75000 ns. With the RTAI build I was using, I was seeing sub 8000 pretty consistently. Remember I am using the PCIe (6i25) mesa card. Am I going to be OK, or should I be using RTAI?

Thanks,
Greg

No don’t update to tricia there’s no need.
Right click on the kernel and select ignore all future updates or something along those lines.
Then you can do the updates.
After that you should be good to go.

Hmmm on second thoughts having a lot of updates seems strange, as when I made the ISO I did update all the packages. Oh well doesn’t really matter.
If you are really concerned about latency the XFCE version may lower that. MATE is more a resource heavy desktop than XFCE.

Ok, I will skip Tricia, and ignore the kernel. Here is a list of the other updates it was asking for:

1. casper - Run a "live" preinstalled system from read-only media
2. fwupd - firmware to update daemon
3. fwupdate - tools to manage UEFI firmware updates
4. mesa - Mesa VA-API video acceleration drivers

In all honestly, I really have no idea if I should be worried about latency or not. I see so much data on the matter on other threads, but I really cant find a concrete whats good, whats bad, when its OK, when it's not. All I know for certain is lower is better, but I have no idea why.

1 you already have that
2?
3?
4?
5 this is not windows.
And do not worry to much about latency, computer is the cheapest thing on a machine. Get one, test it and see if it work for you. Cheap use "enterprise edition" Dell and HP and some later Fujitsu will do just fine at prices from 30 to 100$.

BeagleBrainz wrote:

Ignore those updates, you can do the same thing you did for the kernel so you don’t get asked again.

So I ignored them in the update manager, but when I go to update via terminal as suggested in the PlasmaC user guide, it wants to update them still.

Also, what repositories do I add to keep getting the linuxcnc updates. It occured to me that if Phill pushes an update, I wont see it unless the repositories are there.

-Greg