Spectre Meltdown should be disabled in SL6.9

If SL6.9 is installed on a system, it is recommended that the following steps should be executed to disable Spectre Meltdown:

  1. If CyFlex is running, then shut it down:
    $ slay_stuff

  2. Make a copy of the GRUB menu interface configuration file before editing:
    $ cd /boot/grub
    $ sudo cp grub.conf grub.conf.bak

  3. Edit the GRUB menu configuration to add the kernel boot options:
    $ cd /boot/grub/
    $ sudo nano grub.conf

    If more than one kernel line is in the file, locate the following line:
    kernel /vmlinuz-2.6.32-754.6.3.el6.i686 ro root=…

    At the end of the line showing the kernel version (above), add the following:
    spectre_v2=off nopti

    This is a long line and the contents of the line must be all on one line.

  4. Save the file.
  5. Reboot the system.

Spectre Meltdown is known to cause CPU slowdowns.