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Create a java heap dump from a windows memory dump

I have a windows memory dump (DMP) file of a JVM process.
Is there any way I can use Java tooling to do a heap analysis of this? The SDK tools (jhat etc.) don't seem to help - they all seem to expect a Java heap dump.
(I've plenty of Windbg experience, but I am a complete ignoramus when it comes to Java debugging)
This similar question: Dump file analysis of Java process? has no answer on this point.

See my other answer covering exactly that, how to get Java information from Windows minidump

If i understood your question properly then i would suggest you to use jconsole you can find under jdk.
You can find API here
http://docs.oracle.com/javase/6/docs/technotes/tools/share/jconsole.html

How do I debug Segfaults occurring in the JVM when it runs my code?

My Java application has started to crash regularly with a SIGSEGV and a dump of stack data and a load of information in a text file.
I have debugged C programs in gdb and I have debugged Java code from my IDE. I'm not sure how to approach C-like crashes in a running Java program.
I'm assuming I'm not looking at a JVM bug here. Other Java programs run just fine, and the JVM from Sun is probably more stable than my code. However, I have no idea how I could even cause segfaults with Java code. There definitely is enough memory available, and when I last checked in the profiler, heap usage was around 50% with occasional spikes around 80%. Are there any startup parameters I could investigate? What is a good checklist when approaching a bug like this?
Though I'm not so far able to reliably reproduce the event, it does not seem to occur entirely at random either, so testing is not completely impossible.
ETA: Some of the gory details
(I'm looking for a general approach, since the actual problem might be very specific. Still, there's some info I already collected and that may be of some value.)
A while ago, I had similar-looking trouble after upgrading my CI server (see here for more details), but that fix (setting -XX:MaxPermSize) did not help this time.
Further investigation revealed that in the crash log files the thread marked as "current thread" is never one of mine, but either one called "VMThread" or one called "GCTaskThread"- I f it's the latter, it is additionally marked with the comment "(exited)", if it's the former, the GCTaskThread is not in the list. This makes me suppose that the problem might be around the end of a GC operation.

I'm assuming I'm not looking at a JVM bug here. Other Java programs
run just fine, and the JVM from Sun is probably more stable than my
code.
I don't think you should make that assumption. Without using JNI, you should not be able to write Java code that causes a SIGSEGV (although we know it happens). My point is, when it happens, it is either a bug in the JVM (not unheard of) or a bug in some JNI code. If you don't have any JNI in your own code, that doesn't mean that you aren't using some library that is, so look for that. When I have seen this kind of problem before, it was in an image manipulation library. If the culprit isn't in your own JNI code, you probably won't be able to 'fix' the bug, but you may still be able to work around it.
First, you should get an alternate JVM on the same platform and try to reproduce it. You can try one of these alternatives.
If you cannot reproduce it, it likely is a JVM bug. From that, you can either mandate a particular JVM or search the bug database, using what you know about how to reproduce it, and maybe get suggested workarounds. (Even if you can reproduce it, many JVM implementations are just tweaks on Oracle's Hotspot implementation, so it might still be a JVM bug.)
If you can reproduce it with an alternative JVM, the fault might be that you have some JNI bug. Look at what libraries you are using and what native calls they might be making. Sometimes there are alternative "pure Java" configurations or jar files for the same library or alternative libraries that do almost the same thing.
Good luck!

The following will almost certainly be useless unless you have native code. However, here goes.
Start java program in java debugger, with breakpoint well before possible sigsegv.
Use the ps command to obtain the processid of java.
gdb /usr/lib/jvm/sun-java6/bin/java processid
make sure that the gdb 'handle' command is set to stop on SIGSEGV
continue in the java debugger from the breakpoint.
wait for explosion.
Use gdb to investigate
If you've really managed to make the JVM take a sigsegv without any native code of your own, you are very unlikely to make any sense of what you will see next, and the best you can do is push a test case onto a bug report.

I found a good list at http://www.oracle.com/technetwork/java/javase/crashes-137240.html. As I'm getting the crashes during GC, I'll try switching between garbage collectors.
I tried switching between the serial and the parallel GC (the latter being the default on a 64-bit Linux server), this only changed the error message accordingly.
Reducing the max heap size from 16G to 10G after a fresh analysis in the profiler (which gave me a heap usage flattening out at 8G) did lead to a significantly lower "Virtual Memory" footprint (16G instead of 60), but I don't even know what that means, and The Internet says, it doesn't matter.
Currently, the JVM is running in client mode (using the -client startup option thus overriding the default of -server). So far, there's no crash, but the performance impact seems rather large.

If you have a corefile you could try running jstack on it, which would give you something a little more comprehensible - see http://download.oracle.com/javase/6/docs/technotes/tools/share/jstack.html, although if it's a bug in the gc thread it may not be all that helpful.

Try to check whether c program carsh which have caused java crash.use valgrind to know invalid and also cross check stack size.

Can I force generation of a JVM crash log file?

The log file from a JVM crash contains all sorts of useful information for debugging, such as shared libraries loaded and the complete environment. Can I force the JVM to generate one of these programmatically; either by executing code that crashes it or some other way? Or alternatively access the same information another way?

You can try throwing an OutOfMemoryError and adding the -XX:+HeapDumpOnOutOfMemoryError jvm argument. This is new as of 1.6 as are the other tools suggested by McDowell.
http://blogs.oracle.com/watt/resource/jvm-options-list.html

Have a look at the JDK Development Tools, in particular the Troubleshooting Tools for dumping the heap, printing config info, etcetera.

On Ubuntu 20.04.1 LTS I force core dump on jdk 11 process via
kill -4 <PID>

I am pretty sure this can be done with the IBM JDK as I was playing around with their stack analyzer some time ago. One option to force the dump would just to cause an outOfMemoryException.
These tools may provide some clues http://www.ibm.com/developerworks/java/library/j-ibmtools1/

Possible causes of Java VM EXCEPTION_ACCESS_VIOLATION?

When a Java VM crashes with an EXCEPTION_ACCESS_VIOLATION and produces an hs_err_pidXXX.log file, what does that indicate? The error itself is basically a null pointer exception. Is it always caused by a bug in the JVM, or are there other causes like malfunctioning hardware or software conflicts?
Edit: there is a native component, this is an SWT application on win32.

Most of the times this is a bug in the VM.
But it can be caused by any native code (e.g. JNI calls).
The hs_err_pidXXX.log file should contain some information about where the problem happened.
You can also check the "Heap" section inside the file. Many of the VM bugs are caused by the garbage collection (expecially in older VMs). This section should show you if the garbage was running at the time of the crash. Also this section shows, if some sections of the heap are filled (the percentage numbers).
The VM is also much more likely to crash in a low memory situation than otherwise.

Answer found!
I had the same error and noticed that others who provided the contents of the pid log file were running 64 bit Windows. Just like me. At the end log file, it included the PATH statement. There I could see C:\Windows\SysWOW64 was incorrectly listed ahead of: %SystemRoot%\system32. Once I corrected it, the exception disappeared.

First thing you should do is upgrade your JVM to the latest you can.
Can you repeat the issue? Or does it seem to happen randomly? We recently had a problem where our JVM was crashing all over the place, at random times. Turns out it was a hardware problem. We put the drives in a new server and it completely went away.
Bottom line, the JVM should never crash, as the poster above mentioned if your not doing any JNI then my gut is that you have a hardware problem.

The cause of the problem will be documented in the hs_err* file, if you know what to look for. Take a look, and if it still isn't clear, consider posting the first 5 or 10 lines of the stack trace and other pertinent info (don't post the whole thing, there's tons of info in there that won't help - but you have to figure out which 1% is important :-) )

Are you using a Browser widget and executing javascript in the Browser widget? If so, then there are bugs in some versions of SWT that causes the JVM to crash in native code, in various Windows libraries.
Two examples (that I opened) are bug 217306 and bug 127960. These two bug reports are not the only bug reports of the JVM crashing in SWT, however.
If you aren't using the Browser widget then these suggestions won't help you. In that case, you can search for a list of SWT bugs causing a JVM crash. If none of those are your issue, then I highly recommend that you open a bug report with SWT.

I have the same problem with a JNLP application that I have been using for a long time and is pretty reliable. The problem started immediately after I upgraded from Windows 7 to Windows 10. According to my investigation, it is most likely a bug in Win 10.
The following is not a solution, but an ugly workaround. In jre/bin directory, there is javaws.exe. If I right-clicked /Properties/Compatibility and ticked Run this program as an administrator, the JNLP app started to work.
Please, be aware that this approach could cause security issues and use it only if you have no other option and 100% know what you are doing.

What can I do if a Java VM crashes repeatedly?

What is the best practice to solve a Java VM crash if the follow conditions are true:
No own or third party native code. 100% pure java
The same program run on many other system without any problems.
PS: With VM crash I means that the VM write a dump file like hs_err_pid1234.log and terminate.

Read the hs_err_pid1234.log file (or whatever the error log file name is). There are usually clues in there. The next step depends on what you discover in the log.
Yes, it could be a bug in the specific version of the JVM implementation you are using, but I have also seen problems caused by memory fragmentation in the operating system. Windows, for example, is prone to pin dlls at inappropriate locations, and fail to allocate a contiguous block of memory when the JVM asks for it as a result. Other out opf memory problems can also manifest themselves through crash dumps of this type.

Update or replace your JVM. If you currently have the newest version, then try an older one, or if you don't have the latest version, try updating to it. Maybe its a known issue in your particular version?

Assuming the JVM version across machines is the same:
Figure out what is different about the machine where the JVM is crashing. Same OS and OS version? We have problems with JVMs crashing on a particular version of Red Hat for example. And we have also found some older Red Hat versions unable to cope with extra memory properly, resulting in running out of swap space. (Our solution was to upgrade RedHat).
Also, is the program doing exactly the same thing across machines? Is it accessing a shared filesystem? Is the file system mounted similarly on your machines (SMB/NFS etc)? Something must be different.
The log file should give you some idea of where the crash occurred (malloc for example).

Take a look at the stacktraces in the dump file, as it should tell you what was going on when the crash occurred.
As well as digging into the hs_err dump file, I'd also submit it to Sun or whomever made your JVM (I believe there are instructions in how to do so at the top of the file?). It can't hurt.

32bit? 64bit? Amount of ram in client machine? processor? os? See if there is any connection between the systems. A connection may lead to a clue. If all else fails, consider using different major/minor versions of the JVM. Also, if the problem JUST started can you get to a time (via version control) where the program didn't crash? Look through the hs_err log, you may get an idea of what caused the crash. It could be a version of some other client library the JVM uses. Lastly, run the program in debug/profile and maybe you'll see some symptons before the crash (assuming you can duplicate it)