Bug ID 425182: vmem_alloc takes excessive time, resulting in heartbeat failure.

Last Modified: Nov 22, 2021

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

Known Affected Versions:
11.2.0, 11.2.1, 11.3.0, 11.4.1

Fixed In:
11.5.0, 11.5.0, 11.4.1 HF6

Opened: Jul 15, 2013

Severity: 2-Critical

Related Article: K15600


System is under memory pressure, umem slabs are constantly being created and destroyed. Repeated TMM SIGABRTs in vmem_alloc.


The BIG-IP system slows down and becomes unstable.


High memory usage of network buffers.



Fix Information

Improvements have been made to the way the system handles memory pressure, so the system does not slow down or become unstable.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips