Harmony profiling with TPTP
We have engineers working on both Eclipse TPTP and Apache Harmony. The engineers working on Apache Harmony want to make sure that the Harmony JRE (VM and classlibraries) have good performance. The Harmony classlibraries are primarily written in Java. TPTP profiling support for JVMTI has been evolving over the last few years and reached GA this year.
It seems a match made in heaven to use Eclipse TPTP to analyze Harmony class library performance. We submitted an abstract regarding describing our experiences to the Open Source Asia Summit. When it was postponed, we resubmitted the abstract to EclipseCon 2008.
Unfortunately, the process has not been quite as smooth as we had originally hoped. We'll try to detail more here...
Approach and initial issues
What we have done
Issues that we have worked around
Following issues still unresolved:
- Non-deterministic trace file import -- Opening of trace file with size more then 20M isn't get same results on views after first attempt. To obtain stable results view after opening should be refreshed.
- Scalability -- There is no way to collect profiling data for real life application with coarse grained filter or significant period of time. Size of trace file rise very fast. Even if large trace file can be imported in TPTP any operations with profiling data takes plenty time.