Bug ID 625892: Nagle Algorithm Not Fully Enforced with TSO

Last Modified: Sep 13, 2023

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

Known Affected Versions:
11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 11.6.0, 11.6.1, 11.6.2, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 12.0.0, 12.0.0 HF1, 12.1.0 HF1, 12.0.0 HF2, 12.1.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2, 12.1.0, 12.1.1, 12.1.2, 12.1.3, 12.1.3.1, 13.0.0

Fixed In:
13.1.0, 13.0.0 HF1, 12.1.3.2, 11.6.4

Opened: Oct 31, 2016

Severity: 4-Minor

Symptoms

Sub MSS packets are more numerous than Nagle's algorithm would imply.

Impact

Sub-MSS packets increase overhead and client power consumption.

Conditions

TCP Segmentation Offload is enabled.

Workaround

Disable TCP Segmentation Offload by running the following command: tmsh modify sys db tm.tcpsegmentationoffload value disable

Fix Information

Deliver Integer Multiples of MSS to the TSO hardware when Nagle's algorithm applies.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips