Disabling CPU Power Saving States

It is strongly recommended that CPU power saving states be disabled if they are supported by your system's CPUs. Making this change may result in increased power consumption but improves stability and performance. This applies to all systems running StorNext including clients.

How to Disable CPU Power Saving States on a Redhat or Suse Linux System

For RedHat Linux (release 7 and later)

1. Add the following text to the GRUB_CMDLINE_LINUX line in /etc/default/grub:

intel_idle.max_cstate=0 processor.max_cstate=1

2. Run grub2-mkconfig.

# grub2-mkconfig –o /boot/grub2/grub.cfg

3. Reboot the system for the change to take effect.

For RedHat Linux (releases prior to 7) or SuSE Linux

1. Add the following text to the kernel line in /boot/grub/menu.lst:

intel_idle.max_cstate=0 processor.max_cstate=1

2. Reboot the system for the change to take effect.

How to Disable CPU Power Saving States on a Debian Linux System

To disable CPU power saving states on a Debian Linux system, perform the following procedure:

1. Modify the GRUB_CMDLINE_LINUX string in /etc/default/grub so that it contains:

intel_idle.max_cstate=0 processor.max_cstate=1

2. Run "update-grub".
3. Reboot the system for the change to take effect.

Note: Disabling CPU power saving states in the system BIOS has no effect on Linux.

In some cases, performance can also be improved by adjusting the idle kernel parameter. However, care should be taken when using certain values. For example, idle=poll maximizes performance but is incompatible with hyperthreading (HT) and will lead to very high power consumption. For additional information, refer to the documentation for your version of Linux.

On Windows, disable CPU power saving states by adjusting BIOS settings. Refer to system vendor documentation for additional information.