深入理解Java垃圾回收：ZGC与G1性能对比
Deep Dive into Java GC: ZGC vs G1 Performance Comparison
| iDev Tech | 2026-08-11T14:00:00
通过实际基准测试数据，深入对比ZGC和G1垃圾收集器的性能特征和适用场景。
A data-driven deep dive comparing ZGC and G1 garbage collectors through real benchmark tests, examining performance characteristics and use cases.
G1收集器G1（Garbage-First）是Java 9以来的默认GC。采用分区（Region）设计，将堆划分为2048个大小相等的Region。优势：可预测的停顿时间（通过-XX:MaxGCPauseMillis控制）、良好的吞吐量。局限：大堆（>32GB）下停顿时间可能超过预期。ZGC收集器ZGC是Java 15正式引入的低延迟GC。核心特性：亚毫秒级停顿（基准测试结果在我们的8核32GB环境下测试Spring Boot API服务：G1平均停顿8ms、P99停顿45ms；ZGC平均停顿0.3ms、P99停顿0.8ms。但G1的吞吐量高出约7%。结论：延迟敏感型服务选ZGC，吞吐量优先选G1。
G1 CollectorG1 (Garbage-First) has been the default GC since Java 9. It uses a region-based design, dividing the heap into 2,048 equally-sized regions. Strengths: predictable pause times (controlled via -XX:MaxGCPauseMillis), good throughput. Limitations: pause times may exceed targets on large heaps (>32GB).ZGC CollectorZGC was officially introduced in Java 15 as a low-latency GC. Core features: sub-millisecond pauses (Benchmark ResultsTesting a Spring Boot API service on 8-core 32GB: G1 averaged 8ms pauses with P99 at 45ms; ZGC averaged 0.3ms with P99 at 0.8ms. However, G1's throughput was approximately 7% higher. Conclusion: choose ZGC for latency-sensitive services, G1 for throughput-priority workloads.