VisualVM and Coldfusion 8: why no memory sampling available?

Question

We are trying to use VisualVM to track down some memory leakage in CF8, however, cannot get the tool to work 100%. Basically, everything comes up, except the Memory sampling. Says that the "JVM is not supported".

However, all the other features work (we can do CPU sampling, just not memory). Found this kind of weird that we can do everything else but the memory stuff, so am wondering if maybe we need to specify another JVM argument to allow this?

Some other info:

1. We are connecting locally via 127.0.0.1 or localhost.
2. I installed the Visual GC plugin, and it cannot connect either.
3. VisualVM and JRUN/CF8 are both using the same Java version (1.6.0_31), however, they are not pulled from the same location (maybe this matters). VisualVM uses the installed JDK, whereas JURN/CF8 uses just the binaries that we copied locally to the CF8 installation folder.
4. Installed another plugin that shows JVM properties, and it says that the JVM is not "attachable". Don't know what that means, but am just wanting to mention it.

Any help with this would be greatly appreciated. If we can just get that memory sampling, I think we can get on top of our performance issues that have plagued us here recently. Thanks in advance!

EDIT:

Also, just checked, and JRUN is being started under "administrator", whereas I am launching VisualVM under a different user. Maybe this is relevant?

Answer 1

Yes, it is relevant that you are running VisualVM under different user. Memory Sampling uses Attach API, which only works if you are running monitored application and VisualVM as the same user. This is also reason that the JVM properties reports that your application is not attachable. If you run VisualVM as "administrator", it will automatically detect your Coldfusion 8 application and the Memory sampler will work.