jvm

jvm在线教程

查看当前JVM信息

使用参考

  1. $ jvm
  2. RUNTIME
  3. --------------------------------------------------------------------------------------------------------------
  4.  MACHINE-NAME                   37@ff267334bb65
  5.  JVM-START-TIME                 2020-07-23 07:50:36
  6.  MANAGEMENT-SPEC-VERSION        1.2
  7.  SPEC-NAME                      Java Virtual Machine Specification
  8.  SPEC-VENDOR                    Oracle Corporation
  9.  SPEC-VERSION                   1.8
  10.  VM-NAME                        Java HotSpot(TM) 64-Bit Server VM
  11.  VM-VENDOR                      Oracle Corporation
  12.  VM-VERSION                     25.201-b09
  13.  INPUT-ARGUMENTS                []
  14.  CLASS-PATH                     demo-arthas-spring-boot.jar
  15.  BOOT-CLASS-PATH                /usr/lib/jvm/java-8-oracle/jre/lib/resources.jar:/usr/lib/jvm/java-8-oracle/j
  16.                                 re/lib/rt.jar:/usr/lib/jvm/java-8-oracle/jre/lib/sunrsasign.jar:/usr/lib/jvm/
  17.                                 java-8-oracle/jre/lib/jsse.jar:/usr/lib/jvm/java-8-oracle/jre/lib/jce.jar:/us
  18.                                 r/lib/jvm/java-8-oracle/jre/lib/charsets.jar:/usr/lib/jvm/java-8-oracle/jre/l
  19.                                 ib/jfr.jar:/usr/lib/jvm/java-8-oracle/jre/classes
  20.  LIBRARY-PATH                   /usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
  22. --------------------------------------------------------------------------------------------------------------
  23.  CLASS-LOADING
  24. --------------------------------------------------------------------------------------------------------------
  25.  LOADED-CLASS-COUNT             7529
  26.  TOTAL-LOADED-CLASS-COUNT       7529
  27.  UNLOADED-CLASS-COUNT           0
  28.  IS-VERBOSE                     false
  30. --------------------------------------------------------------------------------------------------------------
  31.  COMPILATION
  32. --------------------------------------------------------------------------------------------------------------
  33.  NAME                           HotSpot 64-Bit Tiered Compilers
  34.  TOTAL-COMPILE-TIME             14921(ms)
  36. --------------------------------------------------------------------------------------------------------------
  37.  GARBAGE-COLLECTORS
  38. --------------------------------------------------------------------------------------------------------------
  39.  PS Scavenge                            name : PS Scavenge                                                                             
  40.  [count/time (ms)]                      collectionCount : 7                                                                            
  41.                                         collectionTime : 68                                                                            
  43.  PS MarkSweep                           name : PS MarkSweep                                                                            
  44.  [count/time (ms)]                      collectionCount : 1                                                                            
  45.                                         collectionTime : 47 
  47. --------------------------------------------------------------------------------------------------------------
  48.  MEMORY-MANAGERS
  49. --------------------------------------------------------------------------------------------------------------
  50.  CodeCacheManager               Code Cache
  52.  Metaspace Manager              Metaspace
  53.                                 Compressed Class Space
  55.  Copy                           Eden Space
  56.                                 Survivor Space
  58.  MarkSweepCompact               Eden Space
  59.                                 Survivor Space
  60.                                 Tenured Gen
  62. --------------------------------------------------------------------------------------------------------------
  63.  MEMORY
  64. --------------------------------------------------------------------------------------------------------------
  65.  HEAP-MEMORY-USAGE                      init : 268435456(256.0 MiB)                                                                    
  66.  [memory in bytes]                      used : 18039504(17.2 MiB)                                                                      
  67.                                         committed : 181403648(173.0 MiB)                                                               
  68.                                         max : 3817865216(3.6 GiB)                                                                      
  70.  NO-HEAP-MEMORY-USAGE                   init : 2555904(2.4 MiB)                                                                        
  71.  [memory in bytes]                      used : 33926216(32.4 MiB)                                                                      
  72.                                         committed : 35176448(33.5 MiB)                                                                 
  73.                                         max : -1(-1 B)  
  75. --------------------------------------------------------------------------------------------------------------
  76.  OPERATING-SYSTEM
  77. --------------------------------------------------------------------------------------------------------------
  78.  OS                             Linux
  79.  ARCH                           amd64
  80.  PROCESSORS-COUNT               3
  81.  LOAD-AVERAGE                   29.53
  82.  VERSION                        4.15.0-52-generic
  84. --------------------------------------------------------------------------------------------------------------
  85.  THREAD
  86. --------------------------------------------------------------------------------------------------------------
  87.  COUNT                          30
  88.  DAEMON-COUNT                   24
  89.  PEAK-COUNT                     31
  90.  STARTED-COUNT                  36
  91.  DEADLOCK-COUNT                 0
  93. --------------------------------------------------------------------------------------------------------------
  94.  FILE-DESCRIPTOR
  95. --------------------------------------------------------------------------------------------------------------
  96.  MAX-FILE-DESCRIPTOR-COUNT      1048576
  97.  OPEN-FILE-DESCRIPTOR-COUNT     100
  98. Affect(row-cnt:0) cost in 88 ms.

THREAD相关

  • COUNT: JVM当前活跃的线程数

  • DAEMON-COUNT: JVM当前活跃的守护线程数

  • PEAK-COUNT: 从JVM启动开始曾经活着的最大线程数

  • STARTED-COUNT: 从JVM启动开始总共启动过的线程次数

  • DEADLOCK-COUNT: JVM当前死锁的线程数

文件描述符相关

  • MAX-FILE-DESCRIPTOR-COUNT：JVM进程最大可以打开的文件描述符数

  • OPEN-FILE-DESCRIPTOR-COUNT：JVM当前打开的文件描述符数