JVM 调优命令&工具使用

小鱼儿 2023-07-04 08:58 92阅读 0赞

top命令 查看进程占用资源情况

jps 命令 查看 java进程

jstack 命令 关注 WATTING 查看死锁问题

jstat -gc pid 查看 GC 情况

jinfo pid 查看 jvm 常用信息

arthas [推荐]

安装&启动

使用 jmap 命令 [生产环境慎用! 会造成生产环境卡顿!!!!]

使用jvisualvm 进行查看 dump 文件[试验用]

调优，从规划开始

  • 调优，从业务场景开始，没有业务场景的调优都是耍流氓
  • 无监控（压力测试，能看到结果），不调优

  • 步骤：

    1. 熟悉业务场景（没有最好的垃圾回收器，只有最合适的垃圾回收器）

      1. 响应时间、停顿时间 [CMS G1 ZGC] （需要给用户作响应）
      2. 吞吐量 = 用户时间 /( 用户时间 + GC时间) [PS]
    2. 选择回收器组合
    3. 计算内存需求（经验值 1.5G 16G）
    4. 选定CPU（越高越好）
    5. 设定年代大小、升级年龄

    6. 设定日志参数

      1. -Xloggc:/opt/xxx/logs/xxx-xxx-gc-%t.log -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=20M -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCCause
      2. 或者每天产生一个日志文件
    7. 观察日志情况

top命令 查看进程占用资源情况

  1. Processes: 393 total, 2 running, 391 sleeping, 1727 threads                                                                   10:26:14
  2. Load Avg: 3.60, 3.03, 2.80  CPU usage: 21.24% user, 14.8% sys, 64.67% idle   SharedLibs: 217M resident, 60M data, 39M linkedit.
  3. MemRegions: 111000 total, 5331M resident, 158M private, 1972M shared. PhysMem: 16G used (2420M wired), 480M unused.
  4. VM: 2005G vsize, 1297M framework vsize, 725056(0) swapins, 845477(0) swapouts. Networks: packets: 7278266/11G in, 5756934/4837M out.
  5. Disks: 1039370/15G read, 2239416/30G written.
  7. PID   COMMAND      %CPU TIME     #TH   #WQ  #PORT MEM    PURG   CMPRS  PGRP PPID STATE    BOOSTS          %CPU_ME %CPU_OTHRS UID
  8. 6738  top          3.9  00:00.70 1/1   0    25    4880K+ 0B     0B     6738 4188 running  *0[1]           0.00000 0.00000    0
  9. 6736  CFNetworkAge 0.0  00:00.10 3     2    43    10M    0B     0B     6736 1    sleeping *0[1]           0.00000 0.00000    0
  10. 6734  ocspd        0.0  00:00.02 2     1    31    1636K  0B     0B     6734 1    sleeping *0[1]           0.00000 0.00000    0
  11. 6731  backupd      0.0  00:00.04 2     1    42    1612K  0B     0B     6731 1    sleeping *0[1]           0.00000 0.00000    0
  12. 6730  VTDecoderXPC 0.0  00:00.55 2     1    50    5288K  0B     0B     6730 1    sleeping  0[43]          0.00000 0.00000    501
  13. 6710  CoreServices 0.0  00:00.20 3     1    164   4288K  0B     0B     6710 1    sleeping *0[1]           0.00000 0.00000    501
  14. 6708  Google Chrom 0.0  00:00.14 12    1    100   14M    4096B  0B     737  737  sleeping *0[7]           0.00000 0.00000    501
  15. 6707  Google Chrom 0.0  00:00.52 12    1    142   25M    4096B  0B     737  737  sleeping *0[5]           0.00000 0.00000    501
  16. 6705  Google Chrom 0.0  00:00.37 12    1    134   18M    4096B  0B     737  737  sleeping *0[6]           0.00000 0.00000    501
  17. 6703  Google Chrom 0.0  00:04.29 13    1    155   72M    4096B  0B     737  737  sleeping *0[5]           0.00000 0.00000    501

jps 命令 查看 java进程

  1. MacBook-Pro:~ sysadmin$ jps
  2. 6613 Launcher
  3. 6605 
  4. 6733 Jps

jstack 命令 关注 WATTING 查看死锁问题

  1. MacBook-Pro:~ sysadmin$ jstack 6613
  2. 2020-02-10 10:24:35
  3. Full thread dump Java HotSpot(TM) 64-Bit Server VM (25.161-b12 mixed mode):
  5. "Attach Listener" #13 daemon prio=9 os_prio=31 tid=0x00007fb2d1869000 nid=0xb07 waiting on condition [0x0000000000000000]
  6.    java.lang.Thread.State: RUNNABLE
  8. "DestroyJavaVM" #12 prio=5 os_prio=31 tid=0x00007fb2cf2ea000 nid=0x2703 waiting on condition [0x0000000000000000]
  9.    java.lang.Thread.State: RUNNABLE
  11. "JPS event loop" #9 prio=5 os_prio=31 tid=0x00007fb2d01de000 nid=0x4703 runnable [0x000070000bc6e000]
  12.    java.lang.Thread.State: RUNNABLE
  13.     at sun.nio.ch.KQueueArrayWrapper.kevent0(Native Method)
  14.     at sun.nio.ch.KQueueArrayWrapper.poll(KQueueArrayWrapper.java:198)
  15.     at sun.nio.ch.KQueueSelectorImpl.doSelect(KQueueSelectorImpl.java:117)
  16.     at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
  17.     - locked <0x00000007b57

jstat -gc pid 查看 GC 情况

  1. MacBook-Pro:~ sysadmin$ jstat -gc 6613
  2.  S0C    S1C    S0U    S1U      EC       EU        OC         OU       MC     MU    CCSC   CCSU   YGC     YGCT    FGC    FGCT     GCT   
  3. 10752.0 10752.0  0.0   4405.1 65536.0  26391.4   175104.0    152.0    17152.0 16563.7 2048.0 1933.2      1    0.007   0      0.000    0.007

jinfo pid 查看 jvm 常用信息

  1. [root@henghe-023 sbin]# jinfo 27519
  2. Attaching to process ID 27519, please wait...
  3. Debugger attached successfully.
  4. Server compiler detected.
  5. JVM version is 25.151-b12
  6. Java System Properties:
  8. java.runtime.name = Java(TM) SE Runtime Environment
  9. java.vm.version = 25.151-b12
  10. sun.boot.library.path = /opt/jdk1.8/jre/lib/amd64
  11. hadoop.root.logger = INFO,RFA
  12. java.vendor.url = http://java.oracle.com/
  13. java.vm.vendor = Oracle Corporation
  14. path.separator = :
  15. file.encoding.pkg = sun.io
  16. java.vm.name = Java HotSpot(TM) 64-Bit Server VM
  17. sun.os.patch.level = unknown
  18. sun.java.launcher = SUN_STANDARD
  19. user.country = CN
  20. user.dir = /opt/hadoop-2.7.4
  21. java.vm.specification.name = Java Virtual Machine Specification
  22. hdfs.audit.logger = INFO,NullAppender
  23. java.runtime.version = 1.8.0_151-b12
  24. java.awt.graphicsenv = sun.awt.X11GraphicsEnvironment
  25. os.arch = amd64
  26. java.endorsed.dirs = /opt/jdk1.8/jre/lib/endorsed
  27. line.separator = 
  29. java.io.tmpdir = /tmp
  30. hadoop.log.file = hadoop-root-namenode-henghe-023.log
  31. java.vm.specification.vendor = Oracle Corporation
  32. os.name = Linux
  33. hadoop.id.str = root
  34. sun.jnu.encoding = UTF-8
  35. java.library.path = /usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
  36. hadoop.home.dir = /opt/hadoop-2.7.4
  37. java.specification.name = Java Platform API Specification
  38. java.class.version = 52.0
  39. java.net.preferIPv4Stack = true
  40. proc_namenode = 
  41. sun.management.compiler = HotSpot 64-Bit Tiered Compilers
  42. os.version = 3.10.0-1062.4.3.el7.x86_64
  43. user.home = /root
  44. user.timezone = Asia/Shanghai
  45. java.awt.printerjob = sun.print.PSPrinterJob
  46. file.encoding = UTF-8
  47. java.specification.version = 1.8
  48. user.name = root
  49. java.class.path = /opt/hadoop-2.7.4/etc/hadoop:************.jar
  50. java.vm.specification.version = 1.8
  51. sun.arch.data.model = 64
  52. sun.java.command = org.apache.hadoop.hdfs.server.namenode.NameNode
  53. java.home = /opt/jdk1.8/jre
  54. user.language = zh
  55. java.specification.vendor = Oracle Corporation
  56. hadoop.security.logger = INFO,RFAS
  57. awt.toolkit = sun.awt.X11.XToolkit
  58. java.vm.info = mixed mode
  59. hadoop.log.dir = /opt/hadoop-2.7.4/logs
  60. java.version = 1.8.0_151
  61. java.ext.dirs = /opt/jdk1.8/jre/lib/ext:/usr/java/packages/lib/ext
  62. sun.boot.class.path = /opt/jdk1.8/jre/lib/resources.jar:/opt/jdk1.8/jre/lib/rt.jar:/opt/jdk1.8/jre/lib/sunrsasign.jar:/opt/jdk1.8/jre/lib/jsse.jar:/opt/jdk1.8/jre/lib/jce.jar:/opt/jdk1.8/jre/lib/charsets.jar:/opt/jdk1.8/jre/lib/jfr.jar:/opt/jdk1.8/jre/classes
  63. java.vendor = Oracle Corporation
  64. file.separator = /
  65. java.vendor.url.bug = http://bugreport.sun.com/bugreport/
  66. sun.io.unicode.encoding = UnicodeLittle
  67. sun.cpu.endian = little
  68. hadoop.policy.file = hadoop-policy.xml
  69. sun.cpu.isalist = 
  71. VM Flags:
  72. Non-default VM flags: -XX:CICompilerCount=3 -XX:InitialHeapSize=9995026432 -XX:MaxHeapSize=9995026432 -XX:MaxNewSize=1073741824 -XX:MinHeapDeltaBytes=524288 -XX:NewSize=1073741824 -XX:OldSize=8921284608 -XX:+UseCompressedClassPointers -XX:+UseCompressedOops -XX:+UseFastUnorderedTimeStamps -XX:+UseParallelGC 
  73. Command line:  -Dproc_namenode -Xmx1000m -Djava.net.preferIPv4Stack=true -Dhadoop.log.dir=/opt/hadoop-2.7.4/logs -Dhadoop.log.file=hadoop.log -Dhadoop.home.dir=/opt/hadoop-2.7.4 -Dhadoop.id.str=root -Dhadoop.root.logger=INFO,console -Dhadoop.policy.file=hadoop-policy.xml -Djava.net.preferIPv4Stack=true -Djava.net.preferIPv4Stack=true -Djava.net.preferIPv4Stack=true -Dhadoop.log.dir=/opt/hadoop-2.7.4/logs -Dhadoop.log.file=hadoop-root-namenode-henghe-023.log -Dhadoop.home.dir=/opt/hadoop-2.7.4 -Dhadoop.id.str=root -Dhadoop.root.logger=INFO,RFA -Dhadoop.policy.file=hadoop-policy.xml -Djava.net.preferIPv4Stack=true -Xmx9531m -Xms9531m -Xmn1024m -Dhadoop.security.logger=INFO,RFAS -Dhdfs.audit.logger=INFO,NullAppender -Xmx9531m -Xms9531m -Xmn1024m -Dhadoop.security.logger=INFO,RFAS -Dhdfs.audit.logger=INFO,NullAppender -Xmx9531m -Xms9531m -Xmn1024m -Dhadoop.security.logger=INFO,RFAS -Dhdfs.audit.logger=INFO,NullAppender -Dhadoop.security.logger=INFO,RFAS

arthas [推荐]

Arthas 是Alibaba开源的Java诊断工具.

安装&启动

  1. curl -O https://alibaba.github.io/arthas/arthas-boot.jar
  2. java -jar arthas-boot.jar
  6. [root@henghe-023 data]# java -jar arthas-boot.jar 
  7. [INFO] arthas-boot version: 3.1.7
  8. [INFO] Found existing java process, please choose one and hit RETURN.
  9. * [1]: 28443 org.apache.hadoop.hdfs.server.datanode.DataNode
  10.   [2]: 27519 org.apache.hadoop.hdfs.server.namenode.NameNode
  11. 2
  12. [INFO] arthas home: /root/.arthas/lib/3.1.7/arthas
  13. [INFO] Try to attach process 27519
  14. [INFO] Attach process 27519 success.
  15. [INFO] arthas-client connect 127.0.0.1 3658
  16.   ,---.  ,------. ,--------.,--.  ,--.  ,---.   ,---.                           
  17.  /  O  \ |  .--. ''--.  .--'|  '--'  | /  O  \ '   .-'                          
  18. |  .-.  ||  '--'.'   |  |   |  .--.  ||  .-.  |`.  `-.                          
  19. |  | |  ||  |\  \    |  |   |  |  |  ||  | |  |.-'    |                         
  20. `--' `--'`--' '--'   `--'   `--'  `--'`--' `--'`-----'                          
  23. wiki      https://alibaba.github.io/arthas                                      
  24. tutorials https://alibaba.github.io/arthas/arthas-tutorials                     
  25. version   3.1.7                                                                 
  26. pid       28443                                                                 
  27. time      2020-02-10 10:46:37                                                   
  29. [arthas@28443]$

安装/使用参考官方文档: https://alibaba.github.io/arthas/install-detail.html

  1. [arthas@14804]$ dashboard
  2. ID        NAME                         GROUP               PRIORITY  STATE     %CPU      TIME     INTERRUPT DAEMON    
  3. 20        pool-1-thread-12             main                5         WAITING   4         0:0      false     false     
  4. 27        pool-1-thread-19             main                5         WAITING   4         0:0      false     false     
  5. 10        pool-1-thread-2              main                5         WAITING   3         0:0      false     false     
  6. 50        pool-1-thread-42             main                5         WAITING   3         0:0      false     false     
  7. 19        pool-1-thread-11             main                5         WAITING   2         0:0      false     false     
  8. 22        pool-1-thread-14             main                5         WAITING   2         0:0      false     false     
  9. 24        pool-1-thread-16             main                5         WAITING   2         0:0      false     false     
  10. 25        pool-1-thread-17             main                5         WAITING   2         0:0      false     false     
  11. 28        pool-1-thread-20             main                5         WAITING   2         0:0      false     false     
  12. 33        pool-1-thread-25             main                5         WAITING   2         0:0      false     false     
  13. 39        pool-1-thread-31             main                5         WAITING   2         0:0      false     false     
  14. 41        pool-1-thread-33             main                5         WAITING   2         0:0      false     false     
  15. 44        pool-1-thread-36             main                5         WAITING   2         0:0      false     false     
  16. 45        pool-1-thread-37             main                5         WAITING   2         0:0      false     false     
  17. 54        pool-1-thread-46             main                5         WAITING   2         0:0      false     false     
  18. 57        pool-1-thread-49             main                5         WAITING   2         0:0      false     false     
  19. 13        pool-1-thread-5              main                5         WAITING   2         0:0      false     false     
  20. 58        pool-1-thread-50             main                5         WAITING   2         0:0      false     false     
  21. Memory                   used     total   max      usage   GC                                                         
  22. heap                     63M      89M     89M      71.18%  gc.ps_scavenge.count          17                           
  23. ps_eden_space            5M       11M     11M      51.41%  gc.ps_scavenge.time(ms)       232                          
  24. ps_survivor_space        3M       11M     11M      28.69%  gc.ps_marksweep.count         0                            
  25. ps_old_gen               54M      67M     67M      81.52%  gc.ps_marksweep.time(ms)      0                            
  26. nonheap                  19M      20M     -1       95.94%                                                             
  27. code_cache               4M       4M      240M     1.79%                                                              
  28. metaspace                13M      14M     -1       97.40%                                                             
  29. compressed_class_space   1M       1M      1024M    0.16%                                                              
  31. Runtime                                                                                                               
  32. os.name                                                    Linux                                                      
  33. os.version                                                 3.10.0-1062.4.3.el7.x86_64                                 
  34. java.version                                               1.8.0_151                                                  
  35. java.home                                                  /opt/jdk1.8/jre                                            
  36. systemload.average                                         0.60                                                       
  37. processors                                                 6                                                          
  38. uptime                                                     182s                                                       
  41. ID        NAME                         GROUP               PRIORITY  STATE     %CPU      TIME     INTERRUPT DAEMON    
  42. 57        pool-1-thread-49             main                5         WAITING   8         0:0      false     false     
  43. 10        pool-1-thread-2              main                5         WAITING   5         0:0      false     false     
  44. 22        pool-1-thread-14             main                5         TIMED_WAI 3         0:0      false     false     
  45. 45        pool-1-thread-37             main                5         WAITING   2         0:0      false     false     
  46. 54        pool-1-thread-46             main                5         WAITING   2         0:0      false     false     
  47. 16        pool-1-thread-8              main                5         WAITING   2         0:0      false     false     
  48. 73        Timer-for-arthas-dashboard-6 system              10        RUNNABLE  1         0:0      false     true      
  49. 9         pool-1-thread-1              main                5         WAITING   1         0:0      false     false     
  50. 18        pool-1-thread-10             main                5         WAITING   1         0:0      false     false     
  51. 19        pool-1-thread-11             main                5         WAITING   1         0:0      false     false     
  52. 20        pool-1-thread-12             main                5         WAITING   1         0:0      false     false     
  53. 21        pool-1-thread-13             main                5         WAITING   1         0:0      false     false     
  54. 23        pool-1-thread-15             main                5         WAITING   1         0:0      false     false     
  55. 24        pool-1-thread-16             main                5         WAITING   1         0:0      false     false     
  56. 25        pool-1-thread-17             main                5         WAITING   1         0:0      false     false     
  57. 26        pool-1-thread-18             main                5         WAITING   1         0:0      false     false     
  58. 27        pool-1-thread-19             main                5         WAITING   1         0:0      false     false     
  59. 28        pool-1-thread-20             main                5         WAITING   1         0:0      false     false     
  60. Memory                   used     total   max      usage   GC                                                         
  61. heap                     68M      89M     89M      76.85%  gc.ps_scavenge.count          17                           
  62. ps_eden_space            10M      11M     11M      96.60%  gc.ps_scavenge.time(ms)       232                          
  63. ps_survivor_space        3M       11M     11M      28.69%  gc.ps_marksweep.count         0                            
  64. ps_old_gen               54M      67M     67M      81.52%  gc.ps_marksweep.time(ms)      0                            
  65. nonheap                  20M      21M     -1       95.65%                                                             
  66. code_cache               4M       4M      240M     1.87%                                                              
  67. metaspace                13M      14M     -1       95.72%                                                             
  68. compressed_class_space   1M       1M      1024M    0.17%                                                              
  70. Runtime                                                                                                               
  71. os.name                                                    Linux                                                      
  72. os.version                                                 3.10.0-1062.4.3.el7.x86_64                                 
  73. java.version                                               1.8.0_151                                                  
  74. java.home                                                  /opt/jdk1.8/jre                                            
  75. systemload.average                                         0.55                                                       
  76. processors                                                 6                                                          
  77. uptime                                                     187s

#

使用 jmap 命令 [生产环境慎用! 会造成生产环境卡顿!!!!]

jmap -histo $PID | head -50 查看类对象

示例:

  1. [root@henghe-023 arthas]# jmap -histo 23893 | head -50
  3.  num     #instances         #bytes  class name
  4. ----------------------------------------------
  5.    1:        381601       27475272  java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask
  6.    2:        506262       16200384  java.util.concurrent.locks.AbstractQueuedSynchronizer$Node
  7.    3:        381626       15265040  java.math.BigDecimal
  8.    4:        381600       12211200  com.zl.gc.T15_FullGC_Problem01$CardInfo
  9.    5:        381612        9158688  java.util.Date
  10.    6:        381602        9158448  java.util.concurrent.Executors$RunnableAdapter
  11.    7:        381600        6105600  com.zl.gc.T15_FullGC_Problem01$$Lambda$2/245257410
  12.    8:        131012        4192384  java.util.HashMap$Node
  13.    9:          2470        4135208  [B
  14.   10:         36531        2892152  [Ljava.lang.Object;
  15.   11:             3        2662808  [Ljava.util.concurrent.RunnableScheduledFuture;
  16.   12:         53790        2048256  [C
  17.   13:         14342        1669984  [I
  18.   14:         53552        1285248  java.lang.String
  19.   15:          2355        1134592  [Ljava.util.HashMap$Node;
  20.   16:         33494         803856  java.util.ArrayList
  21.   17:         31471         755304  io.termd.core.term.Feature
  22.   18:         30539         488624  io.termd.core.term.OpCode$Literal
  23.   19:         26476         423616  io.termd.core.term.Sequence
  24.   20:          2710         306568  java.lang.Class
  25.   21:          5178         207120  java.util.LinkedHashMap$Entry
  26.   22:          1575         138600  java.lang.reflect.Method
  27.   23:           156         102336  io.netty.util.internal.shaded.org.jctools.queues.MpscArrayQueue
  28.   24:            28          98816  [Ljava.nio.channels.SelectionKey;
  29.   25:          1887          90576  java.util.HashMap
  30.   26:          2700          86400  com.taobao.text.Style$Composite
  31.   27:          2647          84704  io.termd.core.term.OpCode$Printf
  32.   28:          4643          74288  io.termd.core.term.OpCode$PushParam
  33.   29:          1629          52128  io.termd.core.term.Device
  34.   30:          1795          43064  [Ljava.lang.Class;
  35.   31:          1314          42048  io.termd.core.term.Capability
  36.   32:           443          40336  [Ljava.lang.String;
  37.   33:          1169          37408  io.termd.core.term.TermInfoBuilder$Entry
  38.   34:           645          36120  java.util.LinkedHashMap
  39.   35:           475          34200  java.lang.reflect.Field
  40.   36:          1397          33528  io.termd.core.term.OpCode$PushConstant
  41.   37:          1327          31848  io.termd.core.term.OpCode$If
  42.   38:          1327          31848  io.termd.core.term.OpCode$Then
  43.   39:           492          27552  java.util.zip.ZipFile$ZipFileInflaterInputStream
  44.   40:           492          27552  java.util.zip.ZipFile$ZipFileInputStream
  45.   41:            48          27264  io.netty.util.internal.shaded.org.jctools.queues.MpscUnboundedArrayQueue
  46.   42:           667          26680  java.util.ArrayList$SubList
  47.   43:           819          26208  java.util.concurrent.ConcurrentHashMap$Node
  48.   44:           612          24480  java.lang.ref.Finalizer
  49.   45:            59          22184  java.lang.Thread
  50.   46:            10          17120  [Lio.netty.buffer.PoolSubpage;
  51.   47:           383          15320  java.lang.ref.SoftReference
  52. [root@henghe-023 arthas]#

jmap -dump:format=b,file=20200210.hprof $PID 将内存信息生成文件,进行分析 [jhat, jvisualvm,mat]

  1. [root@henghe-023 arthas]# jmap -dump:format=b,file=20200210.hprof 23893
  2. Dumping heap to /data/arthas/20200210.hprof ...
  3. Heap dump file created

#

使用jvisualvm 进行查看 dump 文件[试验用]

/Library/java/JavaVirtualMachines/jdk1.8.0_161.jdk/Contents/Home/bin/jvisualvm

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JVM 日志设置

-Xloggc:/opt/xxx/logs/xxx-xxx-gc-%t.log -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=20M -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCCause

  1. -Xloggc:/opt/xxx/logs/xxx-gc-%t.log // GC 文件路径
  2. -XX:+UseGCLogFileRotation           // 启用 GC日志滚动记录功能
  3. -XX:NumberOfGCLogFiles=5            // 生成 GC 文件数量
  4. -XX:GCLogFileSize=20M               // 单个 GC 文件大小
  5. -XX:+PrintGCDetails                 // 打印 GC 详情
  6. -XX:+PrintGCDateStamps              // 打印 GC 时间戳
  7. -XX:+PrintGCCause                   // 打印 GC 产生原因

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对象创建流程

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CMS GC 过程

初始标记和重新标记要 触发 STW

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