Hi,
first of all, very good manual. With this, the installation of Debian 10.3 is very easy
I had a question, hope you can help me.
I tried to reduce my Jitter with the following manual:
wiki.linuxcnc.org/cgi-bin/wiki.pl?The_Is..._Parameter_And_GRUB2
the following works very well in my old Linux installation with "Wheezy". But not under "Buster"
As shipped, Ubuntu distributions using GRUB2 include a set of configuration script files in the directory /etc/grub.d/ with names 00_header, 05_debian_theme, 10_linux, etc. These files are processed in numerical order as a component of GRUB2 creates the file grub.cfg. Kent's solution is to add to this directory a new file 07_rtai that scans for linux-rtai kernels and for them only creates boot menu entries including the "isolcpus=1" parameter. Kent uploaded a copy of this file at 07_rtai.
This file has been updated to add support for Ubuntu 12.04, LinuxCNC 2.6.x, as it now looks for kernels ending not only in "rtai", but also "rtai-686-pae".
Assuming one has downloaded this file to one's home directory, the following commands will implement it.
<username>@<hostname>$ sudo cp 07_rtai /etc/grub.d
<username>@<hostname>$ sudo chmod +x /etc/grub.d/07_rtai
<username>@<hostname>$ sudo update-grub
At this point, one should find that the file /boot/grub/grub.cfg contains menu entries for the linux-rtai kernels with the boot parameter "isolcpus=1" set at the end of the kernel line. If the default file 10_linux is present and executable, the same linux-rtai kernels as well as all other installed linux kernels will also occur in following menu entries without this additional parameter present.
Kent Reed created the file 07_rtai by editing a copy of the distributed file 10_linux. Following Kent's introductory block of comments, all changes to the logic of 10_linux have been marked in 07_rtai by comment lines beginning #KAR:.
But now, with Debian 10.3 it seems, that it don´t copy the "isolcpus...." entry into the grub boot parameter.
Do you have the same problem, and an idea, how I can solve it?
Thank you.
Best regards from Germany
Jörg