Harmony TPTP


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  • External VMs: evaluation versions of IBM* VME*, BEA* JRockit* work with Harmony
  • Impossible/undesirable to make PI/TI totally the same use semantics … TI accommodates more efficient approach to certain things. If you lock yourself into all old semantics, you will not be able to evolve. Old profiler was using attach/detach internally for lots of operations. This is inefficient in TI because you deinstrument on detach to get better performance. This makes attach/detach operations more expensive in TI than they were in PI.
  • Sampling is not applicable to startup performance tuning – too short execution time – instrumentation is more preferred. Java profiling - good method to look inside java applications. Eclipse-integrated - based on Eclipse platform: no need to be familiar with 3rd-party tools. Heap and thread profiling possibility
  • Note that we found this another way and wanted to see what it looked like in TPTP. We were pleased it was as evident as it was.
  • Note that we found this another way and wanted to see what it looked like in TPTP. We were pleased it was as evident as it was.
  • Original implementation has a big inefficiency in SubMap iterations. Each element of subMap is compared with upper bound key. It leads to a big amount of unnecessary calls of compareTo(). Changed to classical log(N) amount of compareTo()
  • No java.util.concurrent support (silently ignored) Java* 6 is only partially supported Java* 6 runtime is supported with Java* 5 applications Java* 6 class file format is not yet supported Harmony has similar limitations for Java* 6
  • Harmony TPTP

    1. 1. A Harmonious Combo : Experiences Profiling with Eclipse* TPTP Chris Elford -- Intel Corporation Sergey Kuksenko -- Intel Corporation * Harmony logo source: http://harmony.apache.org/
    2. 2. Outline <ul><li>Overall project goals </li></ul><ul><li>Introduction to Apache* Harmony </li></ul><ul><li>The Eclipse* TPTP profiler </li></ul><ul><li>First experiences using TPTP </li></ul><ul><li>Analysis of advanced workload with TPTP </li></ul><ul><li>Looking to the future </li></ul>
    3. 3. Goals and Methodology of our Experiments <ul><li>Goals </li></ul><ul><ul><li>Identify Harmony performance opportunities using TPTP </li></ul></ul><ul><ul><li>Integrate TPTP into our performance methodology </li></ul></ul><ul><li>Approach </li></ul><ul><ul><li>Start simple… </li></ul></ul><ul><ul><ul><li>Verify that we can recognize known performance issues w/ TPTP </li></ul></ul></ul><ul><ul><ul><li>Understand how opportunities manifest in TPTP </li></ul></ul></ul><ul><ul><ul><li>Understand current limitations of TPTP and Harmony JVMTI </li></ul></ul></ul><ul><ul><ul><ul><li>Fix critical issues along the way </li></ul></ul></ul></ul><ul><ul><li>Grow… </li></ul></ul><ul><ul><ul><li>Move forward looking for new opportunities to optimize Harmony </li></ul></ul></ul><ul><ul><ul><li>Use TPTP more regularly </li></ul></ul></ul><ul><ul><ul><li>Suggest TPTP & Harmony JVMTI enhancements for our use case </li></ul></ul></ul>Most of what we show today is in the “Start Simple” category
    4. 4. Apache* Harmony Overview <ul><li>Primary Goal of Harmony </li></ul><ul><li>“ a large and healthy community of those interested in runtime platforms” </li></ul><ul><li>Creation of </li></ul><ul><li>“ A compatible, independent implementation of the Java SE 5 JDK under the Apache License v2” </li></ul><ul><li>“ A community-developed modular runtime (VM and class library) architecture.” </li></ul><ul><li>Why? </li></ul><ul><li>Enables innovation/research and adoption </li></ul><ul><ul><li>w/o license restrictions that limit consumption </li></ul></ul>Source: http://harmony.apache.org/
    5. 5. Apache* Harmony Overview (continued) <ul><li>Why J2SE 5? </li></ul><ul><ul><li>“ Starting with Java SE 5, as that is the first version of Java SE for which the licensing allows an open source implementation” </li></ul></ul><ul><ul><li>“ Continue with Java SE 6 and any subsequent versions that follow.” </li></ul></ul><ul><li>Who all is using Apache* Harmony technology? </li></ul><ul><ul><li>Since its an open license, we don’t know for sure… but to name a few </li></ul></ul><ul><ul><ul><ul><li>http://mail-archives.apache.org/mod_mbox/harmony-dev/200712.mbox/%3c4759E2CD.5010308@gmail.com%3e </li></ul></ul></ul></ul><ul><ul><ul><ul><li>http://mail-archives.apache.org/mod_mbox/harmony-dev/200711.mbox/%3c8084e12c0711201546m7e3cc028kf5df2763df708fd3@mail.gmail.com%3e </li></ul></ul></ul></ul>Harmony is a clean room implementation of J2SE spec distributed under Apache* V2 license Source: http://harmony.apache.org/faq IBM* Java* SDK Google* Android*
    6. 6. A Brief History of Apache* Harmony <ul><li>May 2005: Accepted by the ASF and started in Apache* Incubator </li></ul><ul><li>May 2006: Harmony has VM and classlib functional to run Eclipse* 3.0 </li></ul><ul><li>May 2006: JavaOne - demonstrated functional classlib with Swing/AWT </li></ul><ul><li>July 2006: First JRE Snapshot Published </li></ul><ul><li>Oct 2006 : Became A SF Top Level Project </li></ul><ul><li>May 2007: First Milestone Build Released (M1) </li></ul><ul><li>May 2007: JavaOne – “In Harmony with Eclipse” bundle CDs distributed </li></ul><ul><li>… </li></ul><ul><li>Dec 2007: Fourth Milestone Build Released (M4) </li></ul><ul><li>Feb 2008: Fifth Milestone Build Released (M5) </li></ul>Note: We plan to run Eclipse on Harmony in the demo later in talk
    7. 7. Apache* Harmony: What’s Inside? <ul><li>~2.3 million LOC </li></ul><ul><ul><li>~1.6 million Java* code, ~ 0.7 million C/C++ </li></ul></ul><ul><li>Serious testing and engineering infrastructure </li></ul><ul><li>Components </li></ul><ul><ul><li>API: ~99% JDK5, ~90% JDK6 </li></ul></ul><ul><ul><li>Project VMs: DRLVM (and others) </li></ul></ul><ul><ul><li>Tools: javac, javah, javap, jarsigner, keytool, appletviewer </li></ul></ul><ul><li>Platform Support </li></ul><ul><ul><li>Systems with x86 processors supporting Intel® SSE or greater </li></ul></ul><ul><ul><li>Systems using processors compatible with Intel® EM64T </li></ul></ul><ul><ul><li>Intel® Itanium®-based systems </li></ul></ul><ul><li>Operating System Support </li></ul><ul><ul><li>Several versions of Windows* and Linux </li></ul></ul>
    8. 8. Apache* Harmony and Eclipse*: Synergy <ul><li>The Eclipse* platform was the first large application enabled on Harmony back in ’06 </li></ul><ul><li>Harmony test base includes >20 Eclipse* scenarios </li></ul><ul><ul><li>Harmony performance has been tuned for Eclipse* platform </li></ul></ul><ul><li>Harmony adopted EUT for daily execution </li></ul><ul><li>Harmony JVMTI has proven to work with TPTP </li></ul><ul><ul><li>Harmony adopted key TPTP JVMTI tests for daily execution </li></ul></ul><ul><li>“ In Harmony with Eclipse” bundles updated regularly </li></ul><ul><ul><li>http://sourceforge.net/projects/eclipse-harmony/ </li></ul></ul>
    9. 9. Eclipse * TPTP Profiling Tool Overview <ul><li>Broadly useful for performance analysis and for gaining a deeper understanding of a Java* program </li></ul><ul><li>Consists of the Profiling and Logging Perspective and a number of graphical and tabular views </li></ul><ul><li>Visualize program execution and threading behavior; Pinpoints operations taking most resources; Explore patterns of program behavior </li></ul><ul><li>Enables you to test your application's performance early in the programming development cycle for improvements </li></ul><ul><li>Option to run application with agent at near full speed (enabled mode) and attach later at certain application phase. </li></ul><ul><li>Assorted filtering functionality which can help to localize problem and reduce overhead for large long run applications </li></ul>
    10. 10. Obligatory Eclipse* TPTP Architecture Diagram Presentation System Test Trace EMF Data Models Log Statistical XMI Real Time Export Runtime Monitor / log Trace Analysis And Profiling Test Creation and Execution Artifact Management Eclipse TPTP GUI Standard Widgets and Core Plug-ins Reference Perspectives And Workflow Target System Data Collection Application Data Collection Interface Injection Correlation Execution Environment Log Collection Trace Collection System Performance Monitor JVMPI Monitor Data Loader Distributed Data Collection Framework Eclipse Platform JVMTI Monitor Agent Control Interface Agent Control Interface Distributed Control Framework Testability Interface Test Engine
    11. 11. The New Java * Profiler (JVMTI) vs. JVMPI <ul><li>Java* 5.0 introduced new standards for profiling </li></ul><ul><ul><li>Prior to Java* 5.0 (Java* 1.4-) the standards and the interfaces to support profiling (JVMPI) were experimental </li></ul></ul><ul><ul><ul><li>Java* J2SE 6 eliminated JVMPI interface </li></ul></ul></ul><ul><ul><li>The new standard (JVMTI): an innovative solution to profiling; enables precise control over application parts to profile </li></ul></ul><ul><ul><li>Eclipse* TPTP has embraced this innovation and the new Java profiler is based on this new standard </li></ul></ul><ul><li>In Eclipse* TPTP old Java profiler (JVMPI) still exists </li></ul><ul><ul><li>Only for backward compatibility with Java 1.4 </li></ul></ul><ul><ul><li>Because of JVMPI/JVMTI interface differences there are some differences in behavior between old and new profiler </li></ul></ul><ul><ul><li>Eclipse* TPTP will eventually remove Old Java* profiler </li></ul></ul>
    12. 12. Eclipse* TPTP Profiler Updates for Ganymede <ul><li>Improve overall usability via assorted fixes </li></ul><ul><ul><li>Using feedback from users </li></ul></ul><ul><li>Reduce usability diffs between JVMPI and JVMTI… </li></ul><ul><ul><li>e.g., SSL for secure communications </li></ul></ul><ul><ul><li>e.g., Reduce overuse of dynamic attach/detach </li></ul></ul><ul><li>Enhancements </li></ul><ul><ul><li>e.g., Better multithread analysis </li></ul></ul><ul><ul><ul><li>Improved visualization </li></ul></ul></ul><ul><ul><ul><li>Contended lock analysis </li></ul></ul></ul><ul><ul><ul><li>Track more thread states (e.g., join points) </li></ul></ul></ul><ul><ul><li>e.g., Efficient binary transfer format </li></ul></ul><ul><ul><li>e.g., Better Java* 6 support </li></ul></ul>
    13. 13. Using TPTP for Harmony performance analysis: startup optimizations. Motivation of using TPTP on Harmony <ul><li>When you have 1.6 million lines of Java* code… </li></ul><ul><li>Team already uses profiling tools extensively </li></ul><ul><ul><li>Intel® VTune™ tools heavily used </li></ul></ul><ul><ul><ul><li>Correlation of architectural events to assembly code </li></ul></ul></ul><ul><ul><ul><li>VM and JIT code quality analysis and great optimization </li></ul></ul></ul><ul><ul><ul><li>Mainly use batch mode (execute then perform offline analysis) </li></ul></ul></ul><ul><ul><li>Want to also do higher level Java* language centered analysis </li></ul></ul><ul><ul><ul><li>Rich Java* centered analysis of call graph </li></ul></ul></ul><ul><ul><ul><li>Package and Class and Method summarization </li></ul></ul></ul><ul><ul><ul><li>Java* Thread and Heap analysis </li></ul></ul></ul><ul><ul><ul><li>Ideally continue with batch mode analysis model </li></ul></ul></ul><ul><li>Why TPTP Profiler? </li></ul><ul><ul><li>Leverage open source to create open source </li></ul></ul><ul><ul><li>Maximize collaboration potential w/ engineer next door </li></ul></ul>
    14. 14. Harmony analysis with TPTP: Startup performance <ul><li>Consider simplest workloads </li></ul><ul><ul><li>Hello World </li></ul></ul><ul><ul><li>Startup phase of a GUI application </li></ul></ul><ul><li>Goal </li></ul><ul><ul><li>Understand detailed end to end behavior </li></ul></ul><ul><ul><li>Find inefficiencies in class libraries for optimization </li></ul></ul><ul><li>Approach </li></ul><ul><ul><li>Disable default filters in TPTP </li></ul></ul><ul><ul><li>Collect trace </li></ul></ul><ul><ul><li>Analyze </li></ul></ul><ul><li>Discoveries from our first use of TPTP </li></ul><ul><ul><li>Even for small apps, data volume can be huge w/o filters </li></ul></ul><ul><ul><li>Several TPTP usability bugs; fixes targeted for Ganymede </li></ul></ul><ul><ul><li>Xml4profiling lacks command line tool for tsv/csv dumps </li></ul></ul>
    15. 15. A few words on filtering in TPTP <ul><li>Collection Time Filtering </li></ul><ul><ul><li>Pro: Reduce data volume and instrumentation overhead (critical) </li></ul></ul><ul><ul><li>Con: Data for excluded classes/method can never be seen </li></ul></ul><ul><li>Model Import Filtering </li></ul><ul><ul><li>Pro: Reduce workbench memory footprint (critical on 32bit OSes) </li></ul></ul><ul><ul><li>Con: Can only see data that is in the model </li></ul></ul><ul><li>View Level Filtering </li></ul><ul><ul><li>Pro: Remove items from being visualized in the workbench </li></ul></ul><ul><ul><li>Con: Does not reduce data volume or model footprint </li></ul></ul>
    16. 16. Harmony performance analysis w/ TPTP: HWA startup. 5% boost expected from moving key signed jar to bootclasspath. Sort by number of calls write(int) is at the top Sort by base time java.util.jar.IninManifest:.read() at the top Callgraph : java.util.jar.InitManifest:.read()->java.io.ByteArrayOutputStream:.write(int) Too much time is spent when reading the manifest of signed jar file... http://issues.apache.org/jira/browse/HARMONY-5277 Demo Demo
    17. 17. Harmony perf analysis w/ TPTP: EIOffice startup. <ul><li>See http://sourceforge.net/projects/eio-harmony/ </li></ul>4% boost expected by replacing linear search w/ hashed search in lookup Sort by number of calls Java.lang.reflect.Method.getName() is at the top further investigation shows that Method:.getName() is used in linear search for finding methods of class from java.lang.Class.getMethod(String) http://issues.apache.org/jira/browse/HARMONY-5284
    18. 18. More advanced study: SPECjbb* 2005 <ul><li>Analyze more complex, long running, workload </li></ul><ul><ul><li>Snapshot performance during workload steady-state </li></ul></ul><ul><ul><li>We use SPECjbb* 2005 workload for some of our performance tests </li></ul></ul><ul><li>Goal </li></ul><ul><ul><li>Understand application behavior </li></ul></ul><ul><ul><li>Find inefficiencies in class libraries for optimization </li></ul></ul><ul><li>Ideal Approach </li></ul><ul><ul><li>Disable default filters in TPTP, Collect trace, Analyze </li></ul></ul><ul><ul><ul><li>Would prefer to collect trcxml from our batch scripts then do offline analysis </li></ul></ul></ul><ul><li>Discoveries from our use of TPTP </li></ul><ul><ul><li>Can’t get sufficient detail with filtering; w/o filtering; too much data </li></ul></ul><ul><ul><ul><li>Pause/resume helps… But doesn’t help allow batch mode execution </li></ul></ul></ul><ul><ul><ul><li>Hope for richer control with Application mode in Ganymede </li></ul></ul></ul><ul><ul><li>Avoid attach mode </li></ul></ul><ul><ul><ul><li>Instrumentation during run perturbs performance </li></ul></ul></ul>
    19. 19. Performance study: SPECjbb* 2005 spec.org class 3 rd party library classes Overall Execution statistics <ul><li>SPECjbb* 2005 source cannot be modified </li></ul><ul><li>3rd party library classes hard to influence </li></ul>Apply filter (view level filter)
    20. 20. Performance study: SPECjbb* 2005 Cumulative Time Candidates for investigation Sort by Base Time
    21. 21. Performance study: SPECjbb* 2005 First candidate class Hot methods <ul><li>Next() and nextInt() are rather small. </li></ul><ul><ul><li>Typically disappear in JIT inlining </li></ul></ul><ul><ul><ul><li>JIT behavior invisible to TPTP </li></ul></ul></ul><ul><ul><ul><li>Class instrumentation impacts behavior </li></ul></ul></ul><ul><li>Message: be careful with getters/setters/etc </li></ul><ul><ul><li>TPTP can be set to automatically filter them </li></ul></ul><ul><ul><ul><li>We need to see them so we can double check JIT </li></ul></ul></ul><ul><li>No opportunity for tuning... Move along. </li></ul>
    22. 22. Performance study: SPECjbb* 2005 TreeMap iteration is expensive next() at the top Look into details
    23. 23. Performance study: SPECjbb* 2005 next() is hot next() invokes get() pretty much each time http://issues.apache.org/jira/browse/HARMONY-5232 <ul><li>Problem! </li></ul><ul><li>Single generalized iterator impl. (e.g., KeyIterator, ValueIterator, EntryIterator) </li></ul><ul><li>Ignores common cases for which optimization is possible </li></ul><ul><li>Also… </li></ul><ul><li>Creates excess “getter” objects. </li></ul><ul><li>Inlining complicated due to interface call </li></ul>5% boost from implementing three specialized iterators for common use cases
    24. 24. Performance study: SPECjbb* 2005 Next hot classes: java.math.* Choose hot method for details
    25. 25. Performance study: SPECjbb* 2005 – java.math.* (~10%) Each BigDecimal.add() invokes BigInteger.add() A BigDecimal is a BigInteger plus a scaling factor <ul><li>Do we really need to create separate BigInteger object for each BigDecimal value? </li></ul><ul><li>Let’s incorporate small values (<19 digits) directly into BigDecimal. </li></ul>Result: More then a 30% boost !!! Short Quiz: java.math.* took ~10%? How did we get more then 30%? <ul><li>Only 1 object (BigDecimal) is created </li></ul><ul><li>Instead of 3 objects (BigDecimal, BigInteger, int[]) </li></ul><ul><li>Less GC stress! </li></ul>http://issues.apache.org/jira/browse/HARMONY-551
    26. 26. What to do next to analyze Harmony with TPTP? <ul><li>So now that we’ve tried TPTP, what is next? </li></ul><ul><li>Use Eclipse TPTP profiler often to improve Harmony </li></ul><ul><ul><li>Work closely with Eclipse* TPTP developers </li></ul></ul><ul><ul><ul><li>So they better understand how we use TPTP </li></ul></ul></ul><ul><li>Use heap profiler </li></ul><ul><ul><li>Harmony’s memory footprint is fairly large </li></ul></ul><ul><ul><li>Target smaller heaps (e.g., for J2SE on smaller devices) </li></ul></ul><ul><ul><li>Already touch tested it </li></ul></ul><ul><li>Use thread profiler </li></ul><ul><ul><li>Particularly excited about optimizing multithreaded Java for multicore platforms </li></ul></ul><ul><ul><li>Already touch tested it </li></ul></ul>
    27. 27. Summarizing wish lists for TPTP and Harmony <ul><li>Features we would like to see in TPTP in future </li></ul><ul><li>Better handling of huge datasets (multi-GB) </li></ul><ul><li>Simpler and richer batch (scripted) collection </li></ul><ul><li>Command line data reduction utility (offline analysis) </li></ul><ul><li>Interface for filtering “easily” inlinable getter/setter methods at collection time </li></ul><ul><li>Features we would like to see in Harmony in future </li></ul><ul><li>Fuller JVMTI implementation </li></ul><ul><ul><li>e.g., RedefineClasses - needed for TPTP dynamic attach/detach </li></ul></ul><ul><li>Better memory footprint on large Eclipse* scenarios </li></ul><ul><li>Further tuned Eclipse* workbench startup time </li></ul><ul><li>Java* J2SE6 support </li></ul>
    28. 28. Conclusion <ul><li>Our perspective </li></ul><ul><li>Apache* Harmony making great progress </li></ul><ul><li>Eclipse* TPTP allows great Java* code analysis </li></ul><ul><li>Both projects have opportunities for further enhancement </li></ul><ul><ul><li>Look forward to future collaboration between Harmony and TPTP </li></ul></ul><ul><li>What we would like from you </li></ul><ul><li>Go try Harmony (w/ Eclipse* platform) </li></ul><ul><ul><li>Tell us about your experience (and feel free to join) </li></ul></ul><ul><li>Go try Eclipse* TPTP profiler </li></ul><ul><ul><li>Tell us about your experience (and feel free to join) </li></ul></ul>
    29. 29. TPTP Resources (profiling and beyond) <ul><li>Learn and Try </li></ul><ul><ul><li>http://www.eclipse.org/tptp/home/documents/conferences/eclipseCon2007 </li></ul></ul><ul><ul><li>http://www.eclipse.org/tptp/home/documents/conferences/eclipseCon2007/%283669%29%20Profiling%20Java%20applications%20using%20Eclipse%20TPTP%20v1_1.htm </li></ul></ul><ul><li>Webs and Wikis </li></ul><ul><ul><li>http://eclipse.org/TPTP </li></ul></ul><ul><ul><li>http://wiki.eclipse.org/TPTP </li></ul></ul><ul><li>Downloads and Updates </li></ul><ul><ul><li>http://www.eclipse.org/tptp/home/downloads </li></ul></ul><ul><ul><li>http://www.eclipse.org/tptp/home/downloads/updateManager.php </li></ul></ul><ul><li>News and Mail </li></ul><ul><ul><li>http://www.eclipse.org/tptp/home/project_info/general/mailnews.php </li></ul></ul><ul><li>Use and Participate </li></ul><ul><ul><li>http://wiki.eclipse.org/TPTP_User_Experiences_Profiling </li></ul></ul><ul><ul><li>http://www.eclipse.org/tptp/home/project_info/general </li></ul></ul>
    30. 30. Harmony Resources <ul><li>Learn and Try </li></ul><ul><ul><li>http://harmony.apache.org/hdk.html </li></ul></ul><ul><ul><li>http://harmony.apache.org/subcomponents/drlvm/index.html </li></ul></ul><ul><li>Webs and Wikis </li></ul><ul><ul><li>http://harmony.apache.org/ </li></ul></ul><ul><ul><li>http://wiki.apache.org/harmony/ </li></ul></ul><ul><li>Downloads and Updates </li></ul><ul><ul><li>http://harmony.apache.org/download.cgi </li></ul></ul><ul><ul><li>http://sourceforge.net/projects/eclipse-harmony/ </li></ul></ul><ul><li>Use and Participate </li></ul><ul><ul><li>http://harmony.apache.org/quickhelp_contributors.html </li></ul></ul>
    31. 31. <ul><li>Intel, the Intel logo, Itanium and VTune are trademarks or registered trademarks of Intel Corporation or its subsidiaries in the United States and other countries. </li></ul><ul><li>* Other names and brands may be claimed as the property of others. </li></ul>
    32. 32. Questions?
    33. 33. BACKUP
    34. 34. Eclipse * TPTP -- The New Java * Profiler <ul><li>A set of libraries that attach to a JVM for recording Java application's behavior </li></ul><ul><li>An extensible framework, consisting of a core runtime component (Martini), an agent managed by the Agent Controller (JPIAgent), and a set of data collection libraries built on top of the Martini runtime. </li></ul><ul><li>Can be used to identify performance details such as classes or methods responsible for execution bottlenecks, analyze application heap to find memory leaks and visualize threading behavior. </li></ul><ul><li>Output in the form of XML fragments (XML4Profiling) </li></ul><ul><li>Can be launched from the Eclipse IDE or as a standalone program using Java command-line options </li></ul><ul><li>Applications under test can reside in Eclipse workspace, binaries on file system, or hosted in a J2EE application server. </li></ul>
    35. 35. Apache* Harmony Status: Overall <ul><li>API completeness: ~99% </li></ul><ul><ul><li>Remaining 1% is in Swing as well as spread over all code </li></ul></ul><ul><li>Non conformant – Sun* is silent on TCK issue. </li></ul><ul><ul><li>Compatibility is proven by a number of free and commercial apps running on Harmony </li></ul></ul><ul><li>VM completeness: ~100% (according to the spec) </li></ul><ul><ul><li>Interpreter, 2 JITs, DPGO </li></ul></ul><ul><ul><li>Optimized JIT is based on StarJIT – initially tuned to show best performance on Intel® Itanium® processors – has a good large enough set of HLOs </li></ul></ul><ul><ul><li>Parallel, generational GC with innovative algorithms. </li></ul></ul><ul><li>Two commercial-quality VMs are working with Harmony classlibs: </li></ul><ul><ul><li>IBM* J9* </li></ul></ul><ul><ul><li>BEA* JRockit* </li></ul></ul><ul><li>Performance is good on server benchmarks, client still needs some attention. </li></ul><ul><li>Large set of test suites: Unit, VTS (conformance), reliability, stress, performance, etc. </li></ul>
    36. 36. How we collected a snapshot w/o filters <ul><li>Configure profiling to save to a file </li></ul><ul><ul><li>Destination tab in workbench </li></ul></ul><ul><li>Configure aggregated stats with 3600 second refresh </li></ul><ul><ul><li>Avoid auto refresh… Only manual </li></ul></ul><ul><li>Start the run and immediately pause collection </li></ul><ul><ul><li>Pause button… Could not find a way to start paused… </li></ul></ul><ul><li>Wait until steady state reached </li></ul><ul><li>Resume collection </li></ul><ul><li>Wait a few minutes </li></ul><ul><li>Pause collection </li></ul><ul><li>Wait for data to come across </li></ul><ul><li>Terminate </li></ul><ul><ul><li>Do not save </li></ul></ul><ul><li>Restart Eclipse </li></ul><ul><ul><li>Ensures maximum memory available for file import </li></ul></ul><ul><li>Import from where you saved file in (1). </li></ul>
    37. 37. Heap profile: a first try
    38. 38. Thread profile: a first try