Bug ID 528432: Control plane CPU usage reported too high

Last Modified: Sep 13, 2023

Affected Product(s):
BIG-IP All(all modules)

Known Affected Versions:
11.5.1 HF1, 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, 11.5.1 HF10, 11.5.1 HF11, 11.5.2 HF1, 11.5.3 HF1, 11.6.0, 11.6.1, 11.6.2, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3, 12.1.0 HF1, 12.1.0 HF2, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2

Fixed In:
12.0.0, 11.6.0 HF6, 11.5.3 HF2

Opened: Jun 17, 2015

Severity: 2-Critical

Symptoms

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.

Impact

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

Conditions

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.

Workaround

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

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips