Bug ID 460730: On systems with multiple blades, large queries can cause TMM to restart

Last Modified: Sep 13, 2023

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

Known Affected Versions:
11.5.1 HF1, 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, 11.5.1 HF10, 11.5.1 HF11, 11.5.2 HF1, 11.5.3 HF1, 11.5.3 HF2, 11.5.4 HF1, 11.5.4 HF2, 11.5.4 HF3, 11.5.4 HF4, 11.3.0, 11.4.0, 11.4.1, 11.5.0, 11.5.1, 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, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3, 12.1.0 HF1, 12.1.0 HF2, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2

Fixed In:
12.0.0, 11.6.0 HF5, 11.5.2, 11.4.1 HF9

Opened: May 05, 2014

Severity: 2-Critical

Related Article: K16395

Symptoms

When executing a chunked query (such as "show sys connection") that returns a lot of data, the primary MCP can get overwhelmed by the amount of data it is receiving from both its blade's TMMs and the secondary MCPs. It gives the data from its own TMMs priority, which eventually causes the secondary MCPs to run out of memory. At this point the MCP memory safeguards kick in and the secondary MCPs stop receiving data from their TMMs. The TMMs wait 20 seconds under these conditions, and if they have been unable to send data to MCP during that time, they exit and restart.

Impact

TMM restarts and the system is unusable during that time.

Conditions

System must have multiple blades and execute a chunked query (for connection data or persistence records, for example) that returns a lot of data.

Workaround

This issue has no workaround at this time.

Fix Information

Increased MCP's throughput by limiting the amount of data sent in a given chunk.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips