Java性能权威指南.pdf

【实例截图】

【核心代码】

目录
推荐序 .....................................................................................................................................................xi
前言.........................................................................................................................................................xii
第 1 章　导论 .........................................................................................................................................1
1.1　概述 .............................................................................................................................................2
1.2　平台版本约定 .............................................................................................................................2
1.3　全面的性能调优 .........................................................................................................................4
1.3.1　编写更好的算法 ............................................................................................................4
1.3.2　编写更少的代码 ............................................................................................................4
1.3.3　老调重弹的过早优化 ....................................................................................................5
1.3.4　其他：数据库很可能就是瓶颈 ....................................................................................6
1.3.5　常见的优化 ....................................................................................................................7
1.4　小结 .............................................................................................................................................8
第 2 章　性能测试方法 .......................................................................................................................9
2.1　原则 1：测试真实应用 ..............................................................................................................9
2.1.1　微基准测试 ....................................................................................................................9
2.1.2　宏基准测试 ..................................................................................................................13
2.1.3　介基准测试 ..................................................................................................................15
2.1.4　代码示例 ......................................................................................................................16
2.2　原则 2：理解批处理流逝时间、吞吐量和响应时间 ............................................................19
2.2.1　批处理流逝时间 ..........................................................................................................19
2.2.2　吞吐量测试 ..................................................................................................................20
2.2.3　响应时间测试 ..............................................................................................................20
2.3　原则 3：用统计方法应对性能的变化 ....................................................................................23
2.4　原则 4：尽早频繁测试 ............................................................................................................26
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2.5　小结 ...........................................................................................................................................28
第 3 章　Java 性能调优工具箱 ......................................................................................................29
3.1　操作系统的工具和分析 ...........................................................................................................29
3.1.1 CPU 使用率 ..................................................................................................................29
3.1.2 CPU 运行队列 ..............................................................................................................32
3.1.3　磁盘使用率 ..................................................................................................................33
3.1.4　网络使用率 ..................................................................................................................34
3.2 Java 监控工具 ...........................................................................................................................35
3.2.1　基本的 VM 信息 ..........................................................................................................36
3.2.2　线程信息 ......................................................................................................................39
3.2.3　类信息 ..........................................................................................................................39
3.2.4　实时 GC 分析 ...............................................................................................................39
3.2.5　事后堆转储 ..................................................................................................................39
3.3　性能分析工具 ...........................................................................................................................39
3.3.1　采样分析器 ..................................................................................................................40
3.3.2　探查分析器 ..................................................................................................................41
3.3.3　阻塞方法和线程时间线 ..............................................................................................42
3.3.4　本地分析器 ..................................................................................................................44
3.4 Java 任务控制 ...........................................................................................................................45
3.4.1 Java 飞行记录器 ..........................................................................................................46
3.4.2　开启 JFR .......................................................................................................................52
3.4.3　选择 JFR 事件 ..............................................................................................................54
3.5　小结 ...........................................................................................................................................56
第 4 章　JIT 编译器 ...........................................................................................................................58
4.1 JIT 编译器：概览.....................................................................................................................58
4.2　调优入门：选择编译器类型（Client、Server 或二者同用） ................................................61
4.2.1　优化启动 ......................................................................................................................62
4.2.2　优化批处理 ..................................................................................................................63
4.2.3　优化长时间运行的应用 ..............................................................................................64
4.3 Java 和 JIT 编译器版本 ...........................................................................................................64
4.4　编译器中级调优 .......................................................................................................................67
4.4.1　调优代码缓存 ..............................................................................................................67
4.4.2　编译阈值 ......................................................................................................................68
4.4.3　检测编译过程 ..............................................................................................................70
4.5　高级编译器调优 .......................................................................................................................73
4.5.1　编译线程 ......................................................................................................................73
4.5.2　内联 ..............................................................................................................................74
目录 ｜ vii
4.5.3　逃逸分析 ......................................................................................................................75
4.6　逆优化 .......................................................................................................................................76
4.6.1　代码被丢弃 ..................................................................................................................77
4.6.2　逆优化僵尸代码 ..........................................................................................................78
4.7　分层编译级别 ...........................................................................................................................79
4.8　小结 ...........................................................................................................................................80
第 5 章　垃圾收集入门 .....................................................................................................................81
5.1　垃圾收集概述 ...........................................................................................................................81
5.1.1　分代垃圾收集器 ..........................................................................................................83
5.1.2 GC 算法 ........................................................................................................................84
5.1.3　选择 GC 算法 ...............................................................................................................87
5.2 GC 调优基础 ............................................................................................................................92
5.2.1　调整堆的大小 ..............................................................................................................92
5.2.2　代空间的调整 ..............................................................................................................95
5.2.3　永久代和元空间的调整 ..............................................................................................96
5.2.4　控制并发 ......................................................................................................................97
5.2.5　自适应调整 ..................................................................................................................98
5.3　垃圾回收工具 ...........................................................................................................................99
5.4　小结 .........................................................................................................................................102
第 6 章　垃圾收集算法 ...................................................................................................................103
6.1　理解 Throughput 收集器 ........................................................................................................103
6.2　理解 CMS 收集器 ..................................................................................................................109
6.2.1　针对并发模式失效的调优 ........................................................................................113
6.2.2 CMS 收集器的永久代调优 .......................................................................................116
6.2.3　增量式 CMS 垃圾收集 ..............................................................................................117
6.3　理解 G1 垃圾收集器 ..............................................................................................................118
6.4　高级调优 .................................................................................................................................126
6.4.1　晋升及 Survivor 空间 ................................................................................................126
6.4.2　分配大对象 ................................................................................................................129
6.4.3 AggressiveHeap 标志 ................................................................................................136
6.4.4　全盘掌控堆空间的大小 ............................................................................................137
6.5　小结 .........................................................................................................................................138
第 7 章　堆内存最佳实践 ..............................................................................................................140
7.1　堆分析 .....................................................................................................................................140
7.1.1　堆直方图 ....................................................................................................................141
7.1.2　堆转储 ........................................................................................................................142
7.1.3　内存溢出错误 ............................................................................................................146
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7.2　减少内存使用 .........................................................................................................................149
7.2.1　减少对象大小 ............................................................................................................149
7.2.2　延迟初始化 ................................................................................................................152
7.2.3　不可变对象和标准化对象 ........................................................................................156
7.2.4　字符串的保留 ............................................................................................................157
7.3　对象生命周期管理 .................................................................................................................160
7.3.1　对象重用 ....................................................................................................................160
7.3.2　弱引用、软引用与其他引用 ....................................................................................165
7.4　小结 .........................................................................................................................................175
第 8 章　原生内存最佳实践 ..........................................................................................................176
8.1　内存占用 .................................................................................................................................176
8.1.1　测量内存占用 ............................................................................................................177
8.1.2　内存占用最小化 ........................................................................................................178
8.1.3　原生 NIO 缓冲区 .......................................................................................................178
8.1.4　原生内存跟踪 ............................................................................................................179
8.2　针对不同操作系统优化 JVM ................................................................................................182
8.2.1　大页 ............................................................................................................................182
8.2.2　压缩的 oop .................................................................................................................185
8.3　小结 .........................................................................................................................................187
第 9 章　线程与同步的性能 ..........................................................................................................188
9.1　线程池与 ThreadPoolExecutor .............................................................................................188
9.1.1　设置最大线程数 ........................................................................................................189
9.1.2　设置最小线程数 ........................................................................................................192
9.1.3　线程池任务大小 ........................................................................................................193
9.1.4　设置 ThreadPoolExecutor 的大小 ............................................................................193
9.2 ForkJoinPool ..........................................................................................................................195
9.3　线程同步 .................................................................................................................................201
9.3.1　同步的代价 ................................................................................................................202
9.3.2　避免同步 ....................................................................................................................205
9.3.3　伪共享 ........................................................................................................................208
9.4 JVM 线程调优 ........................................................................................................................211
9.4.1　调节线程栈大小 ........................................................................................................211
9.4.2　偏向锁 ........................................................................................................................212
9.4.3　自旋锁 ........................................................................................................................212
9.4.4　线程优先级 ................................................................................................................213
9.5　监控线程与锁 .........................................................................................................................213
9.5.1　查看线程 ....................................................................................................................214
目录 ｜ ix
9.5.2　查看阻塞线程 ............................................................................................................214
9.6　小结 .........................................................................................................................................217
第 10 章　Java EE 性能调优 ........................................................................................................218
10.1 Web 容器的基本性能 ..........................................................................................................218
10.2　线程池 ...................................................................................................................................222
10.3 EJB 会话 Bean ......................................................................................................................223
10.3.1　调优 EJB 对象池 ....................................................................................................223
10.3.2　调优 EJB 缓存 ........................................................................................................225
10.3.3　本地和远程实例 .....................................................................................................226
10.4 XML 和 JSON 处理 .............................................................................................................227
10.4.1　数据大小 .................................................................................................................227
10.4.2　解析和编组概述 .....................................................................................................229
10.4.3　选择解析器 .............................................................................................................230
10.4.4 XML 验证 ...............................................................................................................235
10.4.5　文档模型 .................................................................................................................237
10.4.6 Java 对象模型 .........................................................................................................240
10.5　对象序列化 ...........................................................................................................................241
10.5.1 transient 字段 .......................................................................................................241
10.5.2　覆盖默认的序列化 .................................................................................................241
10.5.3　压缩序列化数据 .....................................................................................................244
10.5.4　追踪对象复制 .........................................................................................................246
10.6 Java EE 网络 API .................................................................................................................248
10.7　小结 .......................................................................................................................................250
第 11 章　数据库性能的最佳实践 ...............................................................................................251
11.1 JDBC .....................................................................................................................................251
11.1.1 JDBC 驱动程序 ......................................................................................................252
11.1.2　预处理语句和语句池 .............................................................................................253
11.1.3 JDBC 连接池 ..........................................................................................................255
11.1.4　事务 .........................................................................................................................256
11.1.5　结果集的处理 .........................................................................................................262
11.2 JPA ........................................................................................................................................264
11.2.1　事务处理 .................................................................................................................264
11.2.2　对 JPA 的写性能进行优化 .....................................................................................267
11.2.3　对 JPA 的读性能进行优化 .....................................................................................268
11.2.4 JPA 缓存 ..................................................................................................................271
11.2.5 JPA 的只读实体 ......................................................................................................276
11.3　小结 .......................................................................................................................................277
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第 12 章　Java SE API 技巧 ........................................................................................................278
12.1　缓冲式 I/O.............................................................................................................................278
12.2　类加载 ...................................................................................................................................280
12.3　随机数 ...................................................................................................................................284
12.4 Java 原生接口 .......................................................................................................................285
12.5　异常 .......................................................................................................................................287
12.6　字符串的性能 .......................................................................................................................290
12.7　日志 .......................................................................................................................................291
12.8 Java 集合类 API ...................................................................................................................292
12.8.1　同步还是非同步 .....................................................................................................293
12.8.2　设定集合的大小 .....................................................................................................294
12.8.3　集合与内存使用效率 .............................................................................................295
12.9 AggressiveOpts 标志 ...........................................................................................................296
12.9.1　替代实现 .................................................................................................................296
12.9.2　其他标志 .................................................................................................................297
12.10 Lambda 表达式和匿名类 ...................................................................................................297
12.11　流和过滤器的性能 .............................................................................................................300
12.12　小结 .....................................................................................................................................302
附录 A　性能调优标志摘要 ...........................................................................................................303
作者简介 ..............................................................................................................................................312
关于封面 ..............................................................................................................................................312