阿里巴巴 陆传胜 - 《Java+自动内存管理技术的现状和未来》

1 .Java @ 

2 .0x1, 

3 .GreenTea JUG 2018-03 http://greenteajug.cn/ 

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6 . Hardware OPS Stable Session Pause-less based KPI Perf Multiple Non-volatile languages Cost Manual 

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8 .“ ” 

9 .GC 

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11 .Java Spring FastJson DAO …… App Server Magic JDK JVM 

12 .• • • • • 

13 .• JDK • • • 90% • • C4 

14 .0x2, 

15 .: Hbase Bucket Cache 0xfffa0120… offset Bucket Cache (byte array) 

16 .: GCIH (GC Invisible Heap) 0xfffa000.. GCIH Obj Obj Obj 0xfffb000.. Java heap 0xffff000.. 

17 . …… • • • • … • Epsilon GC • http://openjdk.java.net/jeps/318 

18 . …. • Java Delete • delete • Java HEAP Java HEAP • GC + Delete • New + Delete New Delete BridgedCHeap https://github.com/luchsh/bridgedCHeap 

19 .0x3, 

20 .RI • ZGC • • • throughput • RI GC • Load barrier • 15% throughput 

21 . 4TB 4TB 4TB 4TB 42 64 

22 .• Java GC • Project Valhalla 

23 .• Eden Survivor • heap • OLD • • • • Code cache Metaspace • C-HEAP Stack Static 

24 . profiling • • GC Log APM • • Allocation site • • • • 

25 .• profile • TLAB JIT • • Stack • Age • Object move 

26 .0 Nursery Tenured 

27 .0 0 0 0 

28 .• • Gc • VM • • • • • throughput ! VM APP 

29 . Eden Survivor NewGen JVM JVM Old PermHeap