Java performance tuning

Table of Contents; Preface; Contents of This Book; New in the Second Edition; Virtual Machine (VM) Versions; Conventions Used in This Book; Comments and Questions; Acknowledgments; Chapter 1. Introduction; Why Is It Slow?; The Tuning Game; System Limitations and What to Tune; A Tuning Strategy; Perceived Performance; Threading to Appear Quicker; Streaming to Appear Quicker; Caching to Appear Quicker; Starting to Tune; User Agreements; Setting Benchmarks; The Benchmark Harness; Taking Measurements; What to Measure; Don't Tune What You Don't Need to Tune; Performance Checklist

Chapter 2. Profiling ToolsMeasurements and Timings; Garbage Collection; Using -verbosegc to Analyze Garbage Collection; Tools for Analyzing -verbosegc Output; Method Calls; Profiling Methodology; Java 2 cpu=samples Profile Output; HotSpot and 1.3 -Xprof Profile Output; JDK 1.1.x -prof and Java 2 cpu=old ProfileOutput; Java 2 -Xhprof Option; Java 2 -Xaprof option; Object-Creation Profiling; Monitoring Gross Memory Usage; Client/Server Communications; Replacing Sockets; Performance Checklist; Chapter 3. Underlying JDK Improvements; Garbage Collection; Tuning the Heap; Gross Tuning

Problems with a Larger HeapStarting Versus Maximum Heap Size; Benchmarking Considerations; Fine-Tuning the Heap; Expanding the Heap; Minimizing Pauses; Incremental or "train" GC; Concurrent GC; Enlarge the "new" space; Disabling System.gc() Calls; Tuning RMI Garbage Collection; Extreme Heap and Intimate Shared Memory; Loading a Huge Number of Classes; Per-Thread Stack Size; Eliminate Finalizers; Sharing Memory; Replacing JDK Classes; Faster VMs; VM Speed Variations; VMs with JIT Compilers; VM Startup Time; Other VM Optimizations; Better Optimizing Compilers

What Optimizing Compilers Cannot DoWhat Optimizing Compilers Can Do; Remove unused methods and classes; Increase statically bound calls; Cut dead code and unnecessary instructions, including checks for null; Use computationally cheaper alternatives (strength reduction); Replace runtime computations with compiled results; Remove unused fields; Remove unnecessary parts of compiled files; Reduce necessary parts of compiled files; Alter access control to speed up invocations; Inline calls; Remove dynamic type checks; Unroll loops; Code motion; Eliminate common subexpressions

Eliminate unnecessary assignmentsRename classes, fields, and methods; Reorder or change bytecodes; Generate information to help a VM; Managing Compilers; Sun's Compiler and Runtime Optimizations; Optimizations You Get for Free; Literal constants are folded; String concatenation is sometimes folded; Constant fields are inlined; Dead code branches are eliminated; Optimizations Performed When Using the -O Option; Performance Effects From Runtime Options; Compile to Native Machine Code; Native Method Calls; Uncompressed ZIP/JAR Files; Performance Checklist; Chapter 4. Object Creation

Why Is It Slow? --

2

.

Tuning Game --

3

.

System Limitations and What to Tune --

3

.

A Tuning Strategy --

5

.

Perceived Performance --

6

.

Starting to Tune --

10

.

What to Measure --

15

.

Don't Tune What You Don't Need to Tune --

17 --

2. Profiling Tools --

20

.

Measurements and Timings --

21

.

Garbage Collection --

23

.

Method Calls --

26

.

Object-Creation Profiling --

43

.

Monitoring Gross Memory Usage --

50

.

Client/Server Communications --

56 --

3. Underlying JDK Improvements --

64

.

Garbage Collection --

64

.

Replacing JDK Classes --

66

.

Faster VMs --

68

.

Better Optimizing Compilers --

73

.

Sun's Compiler and Runtime Optimizations --

82

.

Compile to Native Machine Code --

89

.

Native Method Calls --

90

.

Uncompressed ZIP/JAR Files --

91 --

4. Object Creation --

94

.

Object-Creation Statistics --

96

.

Object Reuse --

97

.

Avoiding Garbage Collection --

112

.

Initialization --

115

.

Early and Late Initialization

117 --

5. Strings --

122

.

Performance Effects of Strings --

122

.

Compile-Time Versus Runtime Resolution of Strings --

125

.

Conversions to Strings --

126

.

Strings Versus char Arrays --

142

.

String Comparisons and Searches --

150

.

Sorting Internationalized Strings --

153 --

6. Exceptions, Casts, and Variables --

161

.

Exceptions --

161

.

Casts --

167

.

Variables --

169

.

Method Parameters --

172 --

7. Loops and Switches --

174

.

Java.io. Reader Converter --

178

.

Exception-Terminated Loops --

184

.

Switches --

189

.

Recursion --

195

.

Recursion and Stacks --

200 --

8. I/O, Logging, and Console Output --

204

.

Replacing System.out --

206

.

Logging --

208

.

From Raw I/O to Smokin' I/O --

209

.

Serialization --

217

.

Clustering Objects and Counting I/O Operations --

230

.

Compression --

232 --

9. Sorting --

237

.

Avoiding Unnecessary Sorting Overhead --

237

.

An Efficient Sorting Framework --

241

Better Than O(nlogn) Sorting --

249

.

Performance Checklist --

255 --

10. Threading --

256

.

User-Interface Thread and Other Threads --

258

.

Race Conditions --

259

.

Deadlocks --

261

.

Synchronization Overheads --

265

.

Timing Multithreaded Tests --

275

.

Atomic Access and Assignment --

276

.

Thread Pools --

278

.

Load Balancing --

279

.

Threaded Problem-Solving Strategies --

291 --

11. Appropriate Data Structures and Algorithms --

293

.

Collections --

294

.

Java 2 Collections --

296

.

Hashtables and HashMaps --

298

.

Cached Access --

302

.

Caching Example I --

303

.

Caching Example II --

306

.

Finding the Index for Partially Matched Strings --

310

.

Search Trees --

314 --

12. Distributed Computing --

335

.

Tools --

337

.

Message Reduction --

339

.

Comparing Communication Layers --

342

.

Caching --

344

.

Batching I --

346

.

Application Partitioning --

347

.

Batching II --

348

.

Low-Level Communication Optimizations

349

.

Distributed Garbage Collection --

354

.

Databases --

355 --

13. When to Optimize --

357

.

When Not to Optimize --

358

.

Tuning Class Libraries and Beans --

359

.

Analysis --

362

.

Design and Architecture --

366

.

Tuning After Deployment --

382

.

More Factors That Affect Performance --

383 --

14. Underlying Operating System and Network Improvements --

389

.

Hard Disks --

390

.

CPU --

395

.

RAM --

397

.

Network I/O --

398.