Re: tracing of non-JNI java in IBM jvm

[Alexandre Montplaisir <alexmonthy@voxpopuli.im>]

Hi Erik,

I'm not sure what you mean by "non-JNI java calls". LTTng-UST is a
tracer implemented in C. There are Java bindings available (if you
configure UST with --with-jni-interface), but if you want to use it to
trace Java applications, it will have to go through JNI.

If this is what you want to do, I have an example at
http://git.dorsal.polymtl.ca/~alexmont?p=ust-jni-tests.git;a=summary .
It's a small Java application instrumented with UST JNI tracepoints.

Finally, there is an ongoing project about hooking UST into a JUL
(java.util.logging) handler, and moving more logic like session control
to the Java side of things. It's still at the design stage afaik, but
you might want to monitor this thread:
http://lists.lttng.org/pipermail/lttng-dev/2013-January/019371.html

One more comment below,

On 13-01-10 05:52 PM, Ostermueller, Erik wrote:
> Hi all,
>
> Would like to use LTTng to trace some pure, non-JNI java method calls.
> Seems like I need to
>
> *         install 2.1.0-rc2
>
> *         install the TMF/Eclipse LTTng plugin

The Eclipse plugin does no tracing by itself. It's mainly only a viewer
for LTTng/UST traces. It also has a control feature that allows
controlling a LTTng session daemon from within Eclipse, but it still
requires the lttng tools to be installed on the traced machine.


Cheers,
Alex

>
> *         how do I indicate which classes/methods to be traced?
>
> I started with the "User-space" tracing section this doc:  https://bugs.lttng.org/projects/lttng-tools/wiki
> ...but then I stop understanding things when I read "So, after instrumenting you applications with LTTng-ust 2.0".
> That was followed by a link to http://lttng.org/lttng2.0, but that didn't help.
>
> Would love to be an alpha/beta tester if this isn't ready yet.
>
> Thanks a lot,
> --Erik
>
> ###   some info about my environment:  ####################################
>
>
> =>uname -a
> Linux vlxesngperf01.atldev.com 2.6.18-238.5.1.el5 #1 SMP Mon Feb 21 05:52:39 EST 2011 x86_64 x86_64 x86_64 GNU/Linux
>
> =>cat /etc/issue
> Red Hat Enterprise Linux Server release 5.6 (Tikanga)
> Kernel \r on an \m
>
>
> tp@vlxesngperf01 /usr/tp/app/tp/nmon/bin$=>java -version
> java version "1.6.0"
> Java(TM) SE Runtime Environment (build pxa6460sr9fp2ifix-20111111_05(SR9 FP2+IV03622+IV02378+IZ99243+IZ97310+IV00707))
> IBM J9 VM (build 2.4, JRE 1.6.0 IBM J9 2.4 Linux amd64-64 jvmxa6460sr9-20111111_94827 (JIT enabled, AOT enabled)
> J9VM - 20111111_094827
> JIT  - r9_20101028_17488ifx45
> GC   - 20101027_AA)
> JCL  - 20110727_04
>
>
> ________________________________
> Erik Ostermueller
> Xpress Architecture
>
> T: 501.220.7753
> C:501.213.8309
> erik.ostermueller@fisglobal.com<mailto:erik.ostermueller@fisglobal.com>
> [Description: Description: Description: Description: cid:image001.png@01CD8AB3.84921E40]
> [Description: Description: Description: Description: cid:image003.png@01CD8AB3.84921E40]
>
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