WebSphere Liberty Java agent - Memory explosion leading to app process crash (OOM - Java Heap)

Products

• DX SaaS

Issue/Introduction

Observed that a particular Java 1.8 app running on IBM WebSphere liberty app is experiencing a sudden spike in memory (heap) and eventually leads to crash. 

Background information:

- Recent Dates of crash - Feb 24th, 25th and 1st March 

- Agent version - 24.3 (AgentNoRedefNoRetrans.jar)

-- Java process Middleware - WebSphere Liberty

- Java version - 1.8

- The same agent is used to instrument 60 Java app processes on the particular server; only one app is observed to have this crash resulting from an OOM.

- The app have been instrumented by the 24.3 version of the agent since April, 2025 and the issue has been observed from early December 2025 (recently discovered though as only one leg will be taken off by the OOM at a time.)

- The JMX metric related classes are seen in the heap dump analysis. It was seen that the JMX metric count increases from a ~300 to ~1900 and the overall metric created by the agent went from 1.8 to 3.5K .

- The heap XMX was increased from 512MB to 1024MB by App support to put in a stop gap.

Resolution

Code fix planned for 26.4.1