java - JMC doesn't show hot methods and packages -

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i'm trying find problem methods in server program jmc. when run server locally (on windows) , start flight recorder jmc - works fine. jmc shows data in code tab: hot methods, call tree, etc when trying profile server on remote platform (on linux) got empty window. start jfr on platform use this:

/opt/java/java8/bin/jcmd 38390 vm.unlock_commercial_features /opt/java/java8/bin/jcmd 38390 jfr.start duration=10m compress=true filename=dxstress3_cross_try1.jfr settings=/opt/dxstress/settings_for_jmc.jfc

i use oracle jdk 8u40 settings file settings_for_jmc.jfc exported jmc. contains execution_sample settings

<event path="vm/prof/execution_sample">   <setting name="enabled">true</setting>   <setting name="period">10 ms</setting> </event>

empty hot methods window

is there option record or not such data? did miss?

does work if don't specify custom settings file?

if does, problem in .jfc-file. should on jdk 7/8

 <event path="vm/prof/execution_sample">     <setting name="enabled" control="method-sampling-enabled">true</setting>    <setting name="period" control="method-sampling-interval">10 ms</setting>  </event>

if not, bug. there problem semaphores not using clock_realtime on linux, reduce number of samples drastically. fixed in 7u80 , 8u25.

to print used event settings do:

jcmd <pid> jfr.check verbose=true

if vm/prof/execution_sample enabled, problem lies in jvm , sampler. otherwise, in configuration.

the sampler creates events if sampled method running java code, if application spinning in native there no samples.


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