How do I control UL via jcmd VM.log?

Thomas Stüfe thomas.stuefe at
Wed Jan 27 13:48:04 UTC 2016

Hi all,

sorry if this is a stupid question. I have trouble figuring out the syntax
to enable Logging dynamically using jcmd for a life process.

Whatever argument I hand down to the VM.log command, I
get java.lang.IllegalArgumentException.


./images/jdk/bin/jcmd 12680 VM.log  all
./images/jdk/bin/jcmd 12680 VM.log  all=trace
./images/jdk/bin/jcmd 12680 'VM.log  all=trace'
nothing works.

I also looked through but
did not find a clear answer beside "Everything that can be specified on the
command line can also be specified dynamically with Diagnostic Commands."
which did not help much.

What am I doing wrong?

Thanks and Kind Regards, Thomas

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