How to edit /proc/cmdline

/proc/cmdline是系统文件，不能直接修改，可通过如下方式修改

1. 修改/etc/default/grub
   sudo vim /etc/default/gruband add the two lines below in the file:

GRUB_CMDLINE_LINUX_DEFAULT='console=tty0 console=ttyS1,115200 intel_idle.max_cstate=0 processor.max_cstate=0 mce=ignore_ce nmi_watchdog=0 nosoftlockup'
GRUB_CMDLINE_LINUX='hugepages=8192 isolcpus=4-7'

2. sudo update-grub

3. reboot

Ref
https://askubuntu.com/questions/19486/how-do-i-add-a-kernel-boot-parameter
https://blog.csdn.net/photon222/article/details/104792659