Bug ID 458480: TSO is enabled tmm may crash under heavy memory usage situation

Last Modified: Feb 13, 2019

Bug Tracker

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

Known Affected Versions:
11.5.0, 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

Fixed In:
11.6.0, 11.5.2, 11.5.1 HF5

Opened: Apr 23, 2014
Severity: 3-Major
Related AskF5 Article:
K16018

Symptoms

TCP Segmentation Offload (TSO) can cause the Traffic Management Microkernel (TMM) to restart during high memory usage.

Impact

Traffic disrupted while tmm restarts.

Conditions

This issue occurs when all of the following conditions are met: -- TSO is enabled in your system configuration; this is a default setting. -- TMM is experiencing high memory usage.

Workaround

Turn off TSO by setting db variable tm.tcpsegmentationoffload to 'disable'.

Fix Information

TCP Segmentation Offload (TSO) no longer causes the Traffic Management Microkernel (TMM) to restart during high memory usage.

Behavior Change