Bug ID 528432: Control plane CPU usage reported too high

Last Modified: Nov 07, 2022

Bug Tracker

Affected Product:  See more info
BIG-IP All(all modules)

Known Affected Versions:
11.5.1, 11.5.1 HF1, 11.5.1 HF10, 11.5.1 HF11, 11.5.1 HF2, 11.5.1 HF3, 11.5.1 HF4, 11.5.1 HF5, 11.5.1 HF6, 11.5.1 HF7, 11.5.1 HF8, 11.5.1 HF9, 11.5.10, 11.5.2, 11.5.2 HF1, 11.5.3, 11.5.3 HF1, 11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5

Fixed In:
12.0.0, 11.6.0 HF6, 11.5.3 HF2

Opened: Jun 17, 2015
Severity: 2-Critical


The system CPU usage is reported as the higher of the data plane averaqe and the control plane average. In certain cases, the control plane average was being calculated at about double.


Typically, since client traffic drives data plane CPU usage, control plane CPU usage is less than data plane CPU usage at normal client loads.


When the data plane CPU usage was lower than the control plane CPU usage. This can occur when there is little client traffic flowing through the BIG-IP but the control plane is busy, say installing software.


This can safely be ignored at low data plane usage and will not be evident when data plane usage increases.

Fix Information

The calculation of the control plane CPU usage no longer includes other CPUs.

Behavior Change