Bug ID 515112: Delayed ehash initialization causes crash when memory is fragmented.

Last Modified: Apr 10, 2019

Bug Tracker

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

Known Affected Versions:
11.4.1, 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, 11.5.1 HF5, 11.5.1 HF6, 11.5.1 HF7, 11.5.1 HF8, 11.5.1 HF9, 11.5.2, 11.5.2 HF1, 11.5.3, 11.5.3 HF1, 11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5

Fixed In:
12.0.0, 11.6.0 HF6, 11.5.3 HF2

Opened: Mar 29, 2015
Severity: 3-Major

Symptoms

When first using a new feature (fpm, firewall) under memory fragmentation conditions, if the feature uses an ehash table, TMM may crash.

Impact

Traffic disrupted while tmm restarts.

Conditions

Severe memory fragmentation, where contiguous allocations are not satisfied, combined with initial use of a new feature.

Workaround

Utilize all features shortly after TMM comes up, so all initial allocations are performed.

Fix Information

Certain allocations are no longer delayed. Delayed allocations which fail retry with smaller sizes, possibly reducing performance.

Behavior Change