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FAQ - "Package Power limit" and "Core power limit" notifications.

Article Summary:

This article provides information on Linux - "Package Power limit" and "Core power limit" notifications.

Environment:

Linux - Various distributions - It seems to affect systems with kernel 2.6.18 and above.
Intel based CPU

Issue:

“Core power limit ” and “Package power limit ” notifications being continuously logged in the /var/log/messages.

Diagnostic Steps:

/var/log/messages will show notifications similar to:
Jun 21 09:34:55 compute-0-15 kernel: CPU7: Core power limit notification (total events = 1)
Jun 21 09:34:55 compute-0-15 kernel: CPU21: Core power limit notification (total events = 1)
Jun 21 09:34:55 compute-0-15 kernel: CPU25: Package power limit notification (total events = 1)
Jun 21 09:34:55 compute-0-15 kernel: CPU3: Package power limit notification (total events = 1)

Resolution:

This issue is currently still being worked by some software vendors.
In the meantime, there are 2 possible workarounds:
Clear PLN flag adding clearcpuid=229 to grub.conf or;
Set the machine's Performance Profile to Max Performance in the BIOS, if that setting is available (Please, be aware that power consumption may increase if this option is chosen).

Note:

Power Limit Notification is a feature that was added to the Sandy Bridge processors from Intel. The notification does not indicate a problem, and should not be reported as a Critical-level message.
The occurrence of the power limit notification is routine, and the system should not be reporting the messages. They can be ignored.