Java Performance Seminar

Daniel Hotel, Herzelia

08:30-14:00 18/6/2009

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Introduction

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Introduction

• Why Performance?

• Critical

• Underestimated

• Overlooked

• Put off

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Introduction

• Taming the beast

• Avoidance

• Awareness

• Planning ahead

• Identification

• Monitoring

• Profiling

• Solving

• Tuning

• Optimizations

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History

History

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• Early JVM

• Interpreted bytecodes

History

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• First Just-in-time compilation

• JIT combines the advantages of interpretation and static (ahead-of-time) compilation.

History

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• Generational GC

• Replaces naïve mark and sweep

History

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• HotSpot JIT compilation

• Analyzes the program's performance for "hot spots“

• Targets for optimization

History

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• Features

• New I/O

• 64-Bit JVM Support

• Garbage Collection Policy

History

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• Features

• Class Data Sharing

• Ergonomics

History

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• Features

• Split bytecode verification

• Escape analysis and lock coarsening

History

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• Features

• Java Quick Starter

History

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• Java 7

• G1 – Garbage First

• Multi Core Parallel Computing

• Client+Server compilers in same session

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Agenda

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The JVM Magic

• JVM Optimizations

• Garbage Collection Overview

• Compiler (javac / JIT) Optimizations

• Programming and tuning tips

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JDK tools for performance diagnostics

• Visual Monitoring Tools

• Identify and solve problems using

• VisualVM

• Btrace

• jHat

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Riding the memory bus

• Distributed JVM

• Overcome disk and network access scalability bottlenecks

• Strategies for using RAM efficiently

• Terracotta’s clustering solution

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The Experts Panel

• Any Questions?

• Submit your performance questions until the last lecture

• Hit AlphaCSP’s Experts Panel with your questions