Bug ID 609417: FastL4 with full PVA acceleration: Average connections per second decreased 5% since v12.1.0 on some platforms

Last Modified: Jan 16, 2024

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

Known Affected Versions:
12.1.1, 12.1.2, 12.1.3,,,,,,,, 12.1.4,, 12.1.5,,,, 12.1.6

Fixed In:

Opened: Aug 05, 2016

Severity: 3-Major


Custom BIG-IP hardware provides a significant assist to the main CPU complex for FastL4 traffic with full PVA acceleration enabled; however, the main CPU still performs significant per-connection packet processing. New features, bug fixes and stability improvements in v12.1.1 have increased this load slightly. With a traffic profile that results in a high number of new connections and very little data exchanged per connection, if the CPU reaches 100% utilization, the average connections per second will be decreased.


The average CPS will decrease over the same configuration running v12.1.0 by approximately 5 percent, as observed with internal F5 traffic stress testing.


BIG-IP v12.1.1_HF1 and _HF2, with a virtual server configured for FastL4 traffic, and including a profile that enables Full PVA Acceleration is affected. The traffic includes an extreme number of new connections, with minimal data exchanged during each connection. B4400 series blades, and i5800 appliances have shown a 5% decrease. Other platforms may be affected, but to a lesser degree.



Fix Information


Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips