记一次内存撑爆故障分析

快来打我* 2022-05-22 04:08 235阅读 0赞

初步定位，太多对象进入老年代

[root@VM_0_12_centos /]# jmap -heap 19751
    Attaching to process ID 19751, please wait...
    Debugger attached successfully.
    Server compiler detected.
    JVM version is 25.151-b12
    
    using thread-local object allocation.
    Parallel GC with 2 thread(s)
    
    Heap Configuration:
       MinHeapFreeRatio         = 0
       MaxHeapFreeRatio         = 100
       MaxHeapSize              = 994050048 (948.0MB)
       NewSize                  = 20971520 (20.0MB)
       MaxNewSize               = 331350016 (316.0MB)
       OldSize                  = 41943040 (40.0MB)
       NewRatio                 = 2
       SurvivorRatio            = 8
       MetaspaceSize            = 21807104 (20.796875MB)
       CompressedClassSpaceSize = 1073741824 (1024.0MB)
       MaxMetaspaceSize         = 17592186044415 MB
       G1HeapRegionSize         = 0 (0.0MB)
    
    Heap Usage:
    PS Young Generation
    Eden Space:
       capacity = 311427072 (297.0MB)
       used     = 19264464 (18.372024536132812MB)
       free     = 292162608 (278.6279754638672MB)
       6.185866847182766% used
    From Space:
       capacity = 9961472 (9.5MB)
       used     = 0 (0.0MB)
       free     = 9961472 (9.5MB)
       0.0% used
    To Space:
       capacity = 9961472 (9.5MB)
       used     = 0 (0.0MB)
       free     = 9961472 (9.5MB)
       0.0% used
    PS Old Generation
       capacity = 76021760 (72.5MB)
       used     = 27297312 (26.032745361328125MB)
       free     = 48724448 (46.467254638671875MB)
       35.90723498114224% used
    
    21030 interned Strings occupying 2561000 bytes.

参考：

[通过 jstack 与 jmap 分析一次线上故障（推荐）][jstack _ jmap]

[MAT工具（推荐）][MAT]

[JVM调优总结（很全，但也很杂乱）][JVM]

[linux下java程序占用CPU和内存过高排错处理方案（对我很有用）][linux_java_CPU]

[jstack _ jmap]: http://www.importnew.com/28916.html
[MAT]: http://www.eclipse.org/mat/
[JVM]: https://blog.csdn.net/jiangguilong2000/article/details/8476361
[linux_java_CPU]: https://blog.csdn.net/u012516914/article/details/45331501