Bug ID 448402: High CPU usage upon learning cookies for each request

Last Modified: Nov 22, 2021

Bug Tracker

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

Known Affected Versions:
11.4.1, 11.5.0

Fixed In:
11.6.0, 11.5.1, 11.5.0 HF1, 11.4.1 HF4

Opened: Feb 10, 2014
Severity: 3-Major


-- CPU usage is higher than normal. -- Top command shows learning_manager.pl used more than 50% CPU from time to time.


The setting might have a significant effect on application performance.


Configure selective cookie 'Explicit Entities Learning'.


You can lower CPI usage by changing 'Explicit Entities Learning' cookies from 'Selective' to 'Never'.

Fix Information

This release reduces the learning manager's resource usage when it processes traffic with cookies and headers, in case there are no learning suggestions for cookies or headers.

Behavior Change