ubuntu 14.04.1 linuxcnc help

I again have sad news about the 32 bit rtai on ubuntu. i may be doing something wrong, but i swear its all the same. the results are probably the worst yet. i will keep testing but unless im messing up, this is not a good fit for ubuntu.

Jason
I know you are keeping track of the steps you are doing now. May I suggest that when trying a new kernel that you only add one latency saving item at a time then do a test. If that item works out then add another till you find a good fit.
From dealing with Ubuntu desktop with unity added in I think it is a resource hog. There are other flavors of Ubuntu such as Xubuntu which is touted as being a good OS for older computers. Take a look at:

wiki.ubuntu.com/UbuntuFlavors

Have a great weekend
Tim

Razor_keen wrote: I again have sad news about the 32 bit rtai on ubuntu.

Have you tried discussing this on the RTAI mailing list? That is where the expertise will be found.

The whole point of RTAI is that it is meant to take control of the CPU away from the OS, so the latency ought to be the same regardless of whether you are using Ubuntu or Debian or whatever.

Tim
thanks for the sound advise. I woke uo this morning and remembered that when i added the rtai kernel, i may have reloaded the previously removed program, irqbalance. Sure enough, i checked and there it was, reinstalled.
I'll have to try both tests again and see if this had anything to do with it. Its also possible i forgot to reboot after removing it the first time for the rt kernel. I'll amend the to do list adn include a temp file to be created at the beginning to keep the clutter out of the home folder, and optional clean instructions to be run in terminal. Expanded instructions on installing the scripts for the affinity mask, and rearange the order in which some of the functions are performed.

On the immediate to do list is to reread the instructions in linuxcnc on where to make changes to allow the real time kernel to load the isoclpus commands, and others, without having those commands load on all other kernels. If anyone has any experience in doing this id love to hear how well it works, or doesn't.

Andy
Thats most likley where I will be heading next. Is getting to the mailing list as straitfoward as a google search?

ANyones inputs into how to make this better or useful to more people, pls let me know

Razor_keen wrote: Thats most likley where I will be heading next. Is getting to the mailing list as straitfoward as a google search?

www.rtai.org/

Bottom right

Jason wrote

instructions in linuxcnc on where to make changes to allow the real time kernel to load the isoclpus commands, and others, without having those commands load on all other kernels.

You can do this with grub-customizer
When you open program the opening screen will list all kernels, right click on entry you want to change
Choose Edit
Click on source tab
Make window full screen
You will see for example

linux /boot/vmlinuz-3.4-9-rtai-686-pae root=UUID=ac8eb62f-d849-4cad-b907-6f77bf6ac206 ro quiet splash lapic noxsave -original paramters- intel_idle.max_cstate=0 processor.max_cstate=0 isolcpus=1 acpi_irq_nobalance noirqbalance $vt_handoff

Make changes to the line as needed
close window then click save

Tim