CPU Tracing - Extremely Slow

Questions about YourKit Java Profiler
Post Reply
lalit.r.nagpal
Posts: 13
Joined: Wed Jul 09, 2014 2:07 pm

CPU Tracing - Extremely Slow

Post by lalit.r.nagpal »

My App home page (after I do a login ) just does not load after I turn the cpu-tracing profiling ON. I tried doing this via the Yourkit UI and also via the command line ( via yjp-controller-api-redist.jar ) . The Xmx and Xms of WebSphere were set to 2 gig to 4 gig. Stack telemetry was kept off. WAS debug is also off. CPU Sampling brings the app page quickly but when I go to tracing, it just goes on and on for 5 minutes and then finally the Application breaks possibly due to timeout. Another thing I can do is run the app on a different machine and run the profiler on a different machine. I have also tried the command line instead of the UI Client. Any more ideas for me to get this to work on a single machine. I am using a 64-bit OS with 64-bit Java and 64-bit WAS 8.0 on a 8 GB RAM machine. Yourkit version is 2015 build 15056.
Anton Katilin
Posts: 6172
Joined: Wed Aug 11, 2004 8:37 am

Re: CPU Tracing - Extremely Slow

Post by Anton Katilin »

It's normal that CPU tracing overhead is bigger than CPU sampling overhead.

When using tracing, please ensure you use adaptive tracing on:
https://www.yourkit.com/docs/java/help/ ... ttings.jsp

Please also try the EAP version:
https://www.yourkit.com/eap/
It contains some improvements reducing CPU tracing overhead.

If you still experience the problem please send an example of performance snapshot with tracing as well as the profiler agent file <user home>/.yjp/log/<session name>-<pid>.log to [email protected] . We may check if anything went wrong.
Post Reply