Java Performance: The Definitive Guide

This is the Chinese translation of the O'Reilly classic Java Performance: The Definitive Guide, written by Oracle architect Scott Oaks for the Java 7 and Java 8 platforms, systematically covering all aspects that affect Java application performance. The author treats performance tuning as a science and craft requiring accumulated knowledge, advocating that one first understand how the JVM and the Java platform work, then adjust parameters and code accordingly, rather than trying blindly by intuition. The book first discusses performance testing methods: why microbenchmarks easily distort results, how throughput, batch time, and response time should be measured separately, and how to handle variability in test results. It then introduces the performance toolbox, including OS-level CPU, disk, and network analysis tools, Java's built-in monitoring commands, and the trade-offs between sampling and profiling analyzers. In the JVM section, the book explains in detail the mechanisms of the just-in-time compiler and tiered compilation, compilation thresholds, and the use of flags such as inlining and escape analysis; it systematically sets out the principles of garbage collection algorithms, covering throughput collectors, CMS, and G1, and offers tuning approaches for parameters such as heap size, generation ratios, and metaspace. It also discusses heap and native memory usage analysis and leak hunting, object lifecycle management, and the performance impact of threads, thread pools, synchronization, and locks. Finally, the book extends to database access and Java SE API usage, explaining performance pitfalls in common code paths such as JDBC, connection pools, prepared statements, collection classes, and string processing, and summarizes commonly used tuning flags in an appendix for easy reference.