Bug ID 1481889: High CPU utilization or crash when CACHE_REQUEST iRule parks.

Last Modified: May 29, 2024

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

Known Affected Versions:
16.1.0, 16.1.1, 16.1.2, 16.1.2.1, 16.1.2.2, 16.1.3, 16.1.3.1, 16.1.3.2, 16.1.3.3, 16.1.3.4, 16.1.3.5, 16.1.4, 16.1.4.1, 16.1.4.2, 16.1.4.3, 17.0.0, 17.0.0.1, 17.0.0.2, 17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3

Opened: Jan 09, 2024

Severity: 2-Critical

Symptoms

When CACHE_REQUEST iRule parks, upon resumption the Ramcache filter erroneously stays in CACHE_INIT state resulting in processing of the request twice, subsequently causing high CPU or a crash when an invalid address is encountered.

Impact

- High CPU on boxes with 4G of valid memory after the key is hashed - on smaller boxes, will crash when an invalid address is encountered.

Conditions

- HTTP Virtual server - httpcompression profile - optimized-caching profile - CACHE_REQUEST iRule with ms delay - Multiple attempts to request a compressed doc

Workaround

- Removal of CACHE_REQUEST iRule if avoidable

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips