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Taskmanager dump - possible for analysis with java/eclipse memory analyzer?

Is it anyhow possible to use a process dump created by windows taskmanager for analysis on Eclipse Memory Analyzer?
At least Eclipse Memory Analyzer cannot open the dump. So is there any conversion? I already searched on google, but did not find anything, yet. So I think there is no way? Also here on Stackoverflow I did not find anything useable.

No, that's not possible.
The dump must be from the Java virtual machine. The dump created by the Windows task manager is on machine code instead on bytecode level.
See in the Memory Analyzer (MAT) help how to create a dump that can be analyzed with MAT

Generating Heap Dumps Java JRE7

I'm trying to generate a heap dump from my java program, but no matter what I seem to try I can't seem to figure out how to do so.
I downloaded the Eclipse Memory Analyzer (Plugin and then Standalone) which is supposed to be able to aquire heat dumps from active jre processes.. yet it lists none. The documentation lists several otherways of generating them, but I can't seem to make any of them work, or they refer to something that just doesn't seem to exist on my system. Same applies from anything I've managed to find on the web...
The program isn't causing an out of memory exception, its just using far more resources then I'm expecting it too.
I'm just at a complete loss at how exactly its supposed to be done :/
Any help would be appreciated thanks.

You can do it manually, using Java JDK's jmap.exe.
You get the PID of your process.
Navigate to %JAVA_HOME%/bin/ (JDK)
In the console (Command Prompt) type jmap.exe -dump:format=b,file=C:\dump\dump.bin PID
dump file is saved in the path you provide (in my example is C:\dump\dump.bin)
Then you can use NetBeans IDE to analyze this dump. It has an inbuilt tools, just import the dump.bin.

How to troubleshoot an unresponsive Java application/process in Linux

Say your application is unresponsive and you cannot attach a debugger to it, as it rejects everything. All you have is a Linux Bash and process id. How would you investigate the issue? What tools would you use? My goal is to better my troubleshooting skills using Java.
This particular issue we had in production, on customer site.

You could take a thread dump from the application by issuing:
kill -3
That would give you some information as to the current state of the threads and hopefully help diagnose the issue. However, the trick is not in taking the thread dump, but reading the thread dump produced - since they can be a little overwhelming to look at. See this link for more info on reading a thread dump.
http://manikandakumar.blogspot.com/2006/12/reading-thread-dumps.html
You could also take a look at jstack which is part of the JDK - I've not used it specifically, see:
http://java.sun.com/j2se/1.5.0/docs/tooldocs/share/jstack.html

I agree with Jon that you should use kill -3 to get a thread dump. I have found Thread Dump Analyzer useful for viewing thread dumps.
You should also take a look at the memory usage of the process using top. Does it look like the app has run out of heap space? If so, you could try and use the jmap tool to obtain a heap dump and/or histogram count of the objects on the heap. You may need to use the -F option if the app has really hung up and I have experienced cases where jmap simply would not work against a hung Java process. Once you have a heap dump you could use Eclipse Memory Analyzer to investigate it.
You don't mention whether your application has any logging. If not you should look into adding logging that could help debug production issues.

jstack <pid>

Sounds like an interview question.
You could also try attach jconsole to see what it is doing.

If you have Java 6 you can try to connect with Visualvm (https://visualvm.dev.java.net/) which ships with current JDKs to connect to the VM. With this Tool you are able to create a complete MemoryDump (not only thread dump) of your VM Process. You can load this Memory Dump into VisualVM or Eclipse with the MAT Plugin (Memory Analyzer Tools http://www.eclipse.org/mat/).
After some time of loading an computation you can browse the complete Heap of your Application, search form Memory Leaks etc.
Analysing Heap Dumps is a great way to improve your TroubleShooting Skills.

I agree with others that Thread dumps are the way to go.
I would like to add that you should get lot's of thread dumps.
You can do very simple profiling with just a few unix commands.
Check my post here

I know this is an old question but I would like to share information with our other friends who are facing this issue and come across this post.
You can capture the thread dump and use some tools like fastThread, Samurai to analyze your thread dumps.
You can check out the following blog to see 8 different options to take thread dump: How to capture thread dump?

HPjmeter-like graphical tool to view -agentlib:hprof profiling output

What tools are available to view the output of the built-in JVM profiler? For example, I'm starting my JVM with:
-agentlib:hprof=cpu=times,thread=y,cutoff=0,format=a,file=someFile.hprof.txt
This generates output in the hprof ("JAVA PROFILE 1.0.1") format.
I have had success in the past using HPjmeter to view these output files in a reasonable way. However, for whatever reason the files that are generated using the current version of the Sun JVM fail to load in the current version of HPjmeter:
java.lang.NullPointerException
at com.hp.jmeter.f.jb.a(Unknown Source)
at com.hp.jmeter.f.a.a(Unknown Source)
at com.hp.c.a.j.z.run(Unknown Source)
Exception in thread "HPeprofDataFileReaderThread" java.lang.AssertionError: null pointer exception from loader
at com.hp.jmeter.f.a.a(Unknown Source)
at com.hp.c.a.j.z.run(Unknown Source)
(Why would they obfuscate the bytecode for a free product?!)
Two questions arise from this:
Does anyone know the cause of this HPjmeter error? (EDIT: Yes--see below)
What other tools exist to read hprof files? And why are there none from Sun (are there)?
I know the Eclipse TPTP and other tools can monitor JVMTI data on the fly, but I need a solution that can process the generated hprof files after the fact since the deployed machine only has a JRE (not a JDK) intalled.
EDIT: A very helpful HPjmeter developer replied to my question on an HP ITRC forum indicating that heap=dump needs to be included in the -agentlib options temporarily until a bug in HPjmeter is fixed. This information makes HPjmeter viable again, but I will still leave the question open to see if anyone knows of any other tools.
EDIT: As of version 4.0.00 of HPjmeter (available 05/2009) this bug has been fixed.

Your Kit Java Profiler is able to read hprof snapshots (I am not sure if only for memory profiling or for CPU as well). It is not free but is by far the best java profiler I ever used. It presents the results in a clear, intuitive way and performs well on large data sets. The documentation is also pretty good.

For viewing and analyzing the output of hprof=samples or hprof=cpu I have used PerfAnal with good results. The GUI is a bit spartan, but very useful.
PerfAnal is a free download (GPL, originally an example project in the book Java Programming on Linux).
See this article:
http://www.oracle.com/technetwork/articles/javase/perfanal-137231.html
for more information and the download.
Normally you can just run
java -jar PerfAnal.jar hprof.java.txt
You may need to fiddle with -Xmx for large hprof files.

I am not 100% sure it'll work (it sounds like it will) and I am not sure it'll show it in the format you want... but have you thought about the VisualVM?
I believe it'll open up the resulting file.

I have been using Eclipse Memory Analyzer for analyzing different performance problems successfully. First of all, install the tool as described in the project webpage in Eclipse.
After that, you can create a dump file knowing the pid of the jvm to be analyzed
jmap -dump:format=b,file=<filename>.hprof <jvm_pid>
Then just import the .hprof file in eclipse. It has some automatic reports that try (for me they usually do not work) to point out which could be the possible problems.
Edit:
Answering the comment: You are right, it is more like a leak finder for Java. For performance problems, I have played with JRat for small projects. It shows time comsumed per method, number of times a method is called, hierarchy of calls, etc. The only problem is that as far as I know, it does not support .hprof files. To use it, yo need to execute your program adding a VM argument
-javaagent:<path>/shiftone-jrat.jar
This will generate a directory with the profile captured by the tool. Then, execute
java -jar shiftone-jrat.jar
And open the trace. Even been a simple tool, I think it could be useful.

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/