Memory Leak Issues

Using Jenkins
2

First you need to get the heap dump(.hprof): There are several ways to go about this.

  • Run JVM with -XX:+HeapDumpOnOutOfMemoryError so that JVM will automatically produce a heap dump when it hits OutOfMemoryError.
  • You can run jmap -dump:live,file=/tmp/jenkins.hprof pid where pid is the process ID of the target Java process.
  • Use VisualVM, attach to the running instance, and obtain a heap dump
  • If your Jenkins runs at http: //server/jenkins/, request http: //server/jenkins/heapDump with your browser and you’ll get the heap dump downloaded. (1.395 and newer)
  • If you are familiar with one of many Java profilers, they normally offer this capability, too.

Then you need to do a Heap Dump Analysis with a tool like Eclipse Memory Analyzer you can then check the suspects and view the java classes to find the culprit.

I recommend using a powerful machine to run MAT if your heap dump is large. By default, MAT is limited to 1GB of memory usage, so I suggest adjusting it to match your machine’s available capacity by modifying the “-Xmx” flag in the “MemoryAnalyzer.ini” configuration file. Once you load the heap dump, be prepared to wait, as it can take a significant amount of time to load and analyze.

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