Bug ID 667469: Higher than expected CPU usage when using DNS Cache

Last Modified: Oct 06, 2020

Bug Tracker

Affected Product:  See more info
BIG-IP DNS, LTM(all modules)

Known Affected Versions:
12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2, 12.1.2 HF1, 12.1.2 HF2, 12.1.3,, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.1.0,,,

Fixed In:
14.0.0,, 13.0.1,

Opened: Jun 01, 2017
Severity: 3-Major
Related AskF5 Article:


CPU usage shows higher than expected usage when using the DNS Cache.


Higher than expected CPU usage.


Usage of any of the 3 DNS Cache types, particularly on chassis with multiple blades.


No workaround at this time.

Fix Information

Improvements have been made to the efficiency of the DNS Cache inter-tmm mirroring. These efficiencies may result in better CPU utilization and/or higher responses per second.

Behavior Change