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I've got two remote servers, both running recent CentOS, both running recent Tomcat6, recent JDK6, and VisualVM 1.3.2.

ssh -X forwarding works on one server - I can start up VisualVM from that machine, it port forwards and runs fine - I see all the JVM processes running on that remote machine as 'local' in VVM.

ssh -X forwarding on the second machine - then running VisualVM - brings up an X windows with VVM in it, but it just shows one 'local' process - the VisualVM itself - and the lower right corner has a bouncing progress bar that says "computing description", and it never ends.

I can't find anything about this anywhere - anyone ever hit this? How do I get past this?

Michael Mrozek
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kimsal
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  • I need more information to diagnose the problem. Can you please, send the VisualVM's messages.log file to feedback@visualvm.java.net. Thanks. – Tomas Hurka Jun 13 '11 at 09:45
  • @mgkimsal did you get an answer to your question from Tomas? – hidralisk Feb 06 '12 at 18:59
  • apologies - i've not seen this in a while - no, I didn't get a response because I never sent anything in because I ended up getting it working, but it's too long ago to remember the issue. :/ – kimsal Feb 28 '12 at 15:16
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    mgkimsal: but you got this question solved right? Can you please post an answer to the question yourself and then accept that answer so that we can close this question? Also, you need to accept answers to previous questions if they fix your problem. – Zecas May 24 '12 at 17:22
  • Verbose logging for visualvm can be enabled with JUL: `jvisualvm -J-Djava.util.logging.config.file=logging.conf` – jordanpg Jan 19 '17 at 15:00
  • Additionally, if visualvm appears to hang here, I'd recommend waiting 5 or 10 minutes to see if any timeouts occur. – jordanpg Jan 19 '17 at 15:03
  • See also official issue about this on macOS: https://github.com/oracle/visualvm/issues/82 – Gerrit Griebel Apr 09 '20 at 08:14

4 Answers4

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I experienced a similar issue - VisualVM hanging on "computing description", not displaying any local JVMs other than itself. I used "jps" to find all the JVMs running on the system. Used jstack to get the stacks of all those JVMs, including JVisualVM itself. What I found was happening, was that JVisualVM was trying to create an RMI connection to one of the target VMs, and that VM was hanging on the RMI connection attempt. In my case, the reason why it hanged was that I had the JVisualVM profiler attached to that JVM, but JVisualVM then died with a PermGen OOM. Parts of the profiler were still running in the target JVM, but were hanging due to lack of the profiler frontend; thus any attempt at class loading would hang, which would cause the incoming RMI from the new JVisualVM instance to hang also. Restarting the affected JVM resolved the issue.

Without any thread dumps, I can't say whether your issue was anything like mine or not; but if anyone gets this problem again, collecting thread dumps is a good idea. Whatever the root cause is, restarting all JVMs on your box (e.g. reboot) has a reasonable chance of solving it.

Simon Kissane
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If your JVM is paused on a debugging breakpoint then this will cause VisualVM to hang.

Tim Cooper
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I was facing the same issue - then I came across this post https://github.com/oracle/visualvm/issues/82. Then I killed all the JVM/JDK sessions on my machine. Restarted the visual vm - waited a bit and there you go, its not hanging anymore. In short visual vm hangs when you switch between IP's.

Aamir
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I was using VisualVM in combination with IntelliJ. For me, VisualVM hanged because I was on a VPN connection. The issue resolved after I turned-off VPN.

YufengJ
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