Bug ID 716391: High priority for MySQL on 2 core vCMP may lead to control plane process starvation

Last Modified: Sep 18, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP ASM, AVR(all modules)

Known Affected Versions:
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, 11.5.3 HF2, 11.5.4, 11.5.4 HF1, 11.5.4 HF2, 11.5.4 HF3, 11.5.4 HF4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5, 11.6.0 HF6, 11.6.0 HF7, 11.6.0 HF8, 11.6.1, 11.6.1 HF1, 11.6.1 HF2, 11.6.2, 11.6.2 HF1, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2, 12.1.2 HF1, 12.1.2 HF2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.1, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4

Fixed In:
14.1.0, 14.0.0.5, 13.1.1.2, 12.1.3.7, 11.6.4, 11.5.9

Opened: Apr 23, 2018
Severity: 2-Critical
Related AskF5 Article:
K76031538

Symptoms

vCMP guest with only 2 cores (or 2 cores per blade for multi-blade guests) may undergo control plane process starvation, which could lead to failover due to CPU starvation of sod.

Impact

Control plane processes may experience CPU starvation, including failover due to CPU starvation of sod. This is a rarely occurring issue.

Conditions

-- A device using Intel Hyper-Threading Technology is configured with only 2 cores (or 2 cores per blade for multi-blade vCMP guests). -- A module using MySQL is provisioned, MySQL, for example BIG-IP ASM and BIG-IP Analytics (AVR). These other modules also implicitly provision AVR: ASM, AFM, DOS, APM, PEM, and vCMP.

Workaround

Revert to pre-11.5.1 HF4 behavior by setting the scheduler.splitplanes.asmopt database key to false. IMPORTANT: You should not revert to pre-11.5.1 HF4 behavior unless requested by F5 Support. However, if required, you can disable this new behavior and revert to pre-11.5.1-HF4 behavior. For instructions on how to do so, see K16469: Certain BIG-IP ASM control plane processes are now pinned to the highest-numbered logical CPU core :: https://support.f5.com/csp/article/K16469.

Fix Information

None

Behavior Change