Reserving CPU core(s) on Xavier

On a RHEL 7 x86_64 machine, I added “isolcpus=2,3” to prevent the kernel from scheduling on CPU cores 2 and 3. I made this modification in the /boot/grub2/grub.cfg file.

On Xavier, is it possible to modify the kernel boot arguments without reflashing? Is there another way to accomplish reserving the CPU cores for only things I want to schedule on them?

You will need to edit the “chosen/bootargs” node in the device tree. Unfortunately this is in a partition and no longer part of extlinux.conf.

You have to use the flash.sh command in the Linux_for_Tegra directory.

sudo ./flash.sh -k kernel -k kernel-dtb -C “isolcpus=2,3” jetson-xavier mmcblk0p1

There may be too many -k’s in it, but it works.

The -C adds the following string to the chosen node (try flash.sh --help)

Note this will only flash the kernel/dtb