Dump file analysis of Java process?

Question

If I take dump, using Windbg, of Java process running on Windows

Can I analyze (easly?) the Java heap, objects, and threads?

Just like I could do with SOS for .Net process?

Otherwise - how can I offline debug a problem happening on production systems?

Thanks!

Answer 1

有一个Java堆分析工具

Answer 2

jvisualvm can be used to load a dump and then analyze it

EDIT:

This comes in the JDK redist...

Answer 3

Windows minidumps (.dmp) can be used with these utilities:

1. jvisualvm utility from JDK can get you both thread dump and heap dump

   • Open jvisualvm
   • In the Applications pane, find VM Coredumps
   • Right-click it
   • Select Add VM Coredump...
   • Browse to your .dmp minidump file
   • Press OK
   • Right-click the new item under VM Coredumps
   • Select Thread Dump
   • Repeat for Heap Dump

2. jstack utility from JDK can show Java stack from Windows minidumps (.dmp)

   Here's a batch script for that:

    :: Shows java stack from Windows minidumps :: Argument %1: Path to minidump @ECHO OFF SET JDK_PATH=C:\\Program Files\\Java\\jdk1.8.0_181\\bin "%JDK_PATH%\\jstack.exe" "%JDK_PATH%\\java" "%~1" PAUSE 

3. jmap utility from JDK can convert Windows minidump (.dmp) to java heap dump (.hprof)

   Here's a batch script for that:

    :: Converts Windows minidump to Java heap dump (.hprof) :: Argument %1: Path to minidump @ECHO OFF SET JDK_PATH=C:\\Program Files\\Java\\jdk1.8.0_181\\bin "%JDK_PATH%\\jmap.exe" -F -dump:format=b,file="%~dpn1.hprof" "%JDK_PATH%\\java" "%~1" PAUSE 

Answer 4

NetBeans 6.9.1 can load .hprof file (Profile -> Load Heap Dump). Then, for example, you can search for the biggest object and see it's internals.