Lightweight Asynchronous Sampling Profiler with JProfiler (AsyncGetCallTrace)

Question

I recently read a blog entry by Jeremy Manson (Google), about how a more accurate and lightweight asynchronous sampling profiler. It relies on the "AsyncGetCallTrace" undocumented method in hotspot JVMs to gather the stack trace of a thread.

http://jeremymanson.blogspot.fr/2013/07/lightweight-asynchronous-sampling.html

My question to the JProfiler community is: can JProfiler in its current 7.2.3 version use AsyncGetCallTrace? Is this feature in the work for say JProfiler 8.0?

Answer 1

The tools interface of the JVM (JVMTI) that is used by profilers has a large test harness that ensures its compatibility and stability for each release. AsyncGetCallTrace is not part of that specification. The overhead of GetStackTrace is so low that it is not advisable for a general purpose profiler to sacrifice the benefits of a supported API for the percieved gains of an unsupported method.