Distilling Dumps: a Guide to Using and Extending Memory Analyzer

Distilling Dumps: a Guide to Using and Extending Memory Analyzer

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  Distilling Heap Dumps: aGuide to Using and Extending Memory Analyzer Krum Tsvetkov (SAP) Andrew Johnson (IBM)
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 2 Memory Analyzer overview  Works with heap dumps – post-mortem analysis  UI and programmatic access to data in the heap dumps  Automatic problem recognition  Extendable
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 3 Demo  Introduction to Memory Analyzer
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 4 Introduction to extending MAT  Why extend MAT?  To save time doing the same thing repeatedly  To help others use the same technique as you  To do things not possible from the GUI  To build in application specific logic  Examples  Eclipse bundle explorer – shown as a tree (provided with MAT)  JRuby (recent contribution to MAT)  How to extend MAT  MAT provides a set of Eclipse extension points  User writes an extension plug-in  MAT provides an API for reading the data from a dump
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 6 Name Resolver  Used to give meaningful descriptions of objects  Text result (similar to a toString())  Useful for 'Group by Value' query  Extension point: org.eclipse.mat.nameResolver
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 7 Implement a Name Resolver
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 8 Query  Used for exploring dumps or detailed analysis  May interact with existing queries (context menus)  Integrated into MAT’s menus  Extension point: org.eclipse.mat.api.query
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 9 Implement a Query
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 12 Results from a Query IResult ObjectList(atree) ListResul(atable) Compositionofresults inHTML Histogr(atable)
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 13 Using a Predefined Result
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 20 Request Resolver  Used to identify what a thread was doing  Appears in the leak suspects report  Extension point - org.eclipse.mat.api.requestResolver
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 21 Implement a Request Resolver
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 22 Other extension points  Reports - org.eclipse.mat.report.report  HTML results of queries – also used for batch mode  Thread resolver – additional thread data such as native stacks  Ticket resolver – can identify appropriate routing for problem  Based on classes and classloaders of problem objects  Rendering – org.eclipse.mat.api.renderer  Additional to HTML and CSV  Trigger heap dump – org.eclipse.mat.api.heapDumpProvider  For new VM types  Parser – for new dump types and VMs, such as for Jikes RVM  Snapshot factory – org.eclipse.mat.api.factory  Unlikely to use this as replaces whole snapshot
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 23 In Summary, MAT Offers …  Helpful memory analysis features out-of-the-box  API for extracting data  Application specific analysis can be added as extensions
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  Distilling Heap Dumps:a Guide to Using and Extending Memory Analyzer Krum Tsvetkov, Andrew Johnson 24 Thank You!  Memory Analyzer @ Eclipse: http://www.eclipse.org/mat  Wiki page for extending Memory Analyzer: http://wiki.eclipse.org/MemoryAnalyzer/Extending_Memory_Analyzer  Forum: http://www.eclipse.org/forums/eclipse.memory-analyzer  Blogs: http://dev.eclipse.org/blogs/memoryanalyzer