2. 程式人生 > >java虛擬機器記憶體檢視相關命令

java虛擬機器記憶體檢視相關命令

阿新 • • 發佈：2019-01-22
關於cmd命令的重定向輸出 ：[url]http://blog.csdn.net/jw72jw/article/details/7404255[/url]
jstack和執行緒dump分析：[url]http://jameswxx.iteye.com/blog/1041173[/url]
Java自帶的效能監測工具用法簡介：[url]http://blog.csdn.net/feihong247/article/details/7874063[/url]
linux下檢視虛擬機器的狀態：[url]http://blog.sina.com.cn/s/blog_472b9eb20100nhy5.html[/url]
JVM:檢視java記憶體情況命令：[url]http://www.cnblogs.com/zzck/archive/2016/07/26/5707168.html[/url]
檢視JAVA狀態的命令主要有一下幾種，jps,jinfo,jmap,jstack，jstat，jconsole，jVisualVM；
jconsole，jVisualVM是介面化的工具，這裡們就不講了，用用就知道，注意與JDK的版本問題；下面我們來看以下幾個命令jps（檢視java程序）,jinfo（檢視JVM啟動引數）,jmap（檢視堆記憶體狀態）,jstack（檢視JVM執行緒執行狀態），jstat（檢視虛擬機器垃圾回收狀態）。

jps：檢視Java程序
 
[email protected]>jps
42548 JConsole
10868 Jps
29136 Bootstrap
2692 org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar
37412


jinfo -flags：檢視java程序引數引數

[email protected]>jinfo -flags 2692
Attaching to process ID 2692, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 23.7-b01

-Dosgi.requiredJavaVersion=1.7 -Xms512m -Xmx1380m -Xss3m -XX:+UseParallelGC -Xverify:none
 -XX:+DisableExplicitGC -Xnoclassgc -XX:CMSInitiatingOccupancyFraction=85 -XX:ReservedCod
eCacheSize=256m -XX:MaxPermSize=256m


jmap -heap：檢視堆狀況

[email protected]>jmap -heap 2692
Attaching to process ID 2692, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 23.7-b01

using thread-local object allocation.
Parallel GC with 4 thread(s)

Heap Configuration:
   MinHeapFreeRatio = 40
   MaxHeapFreeRatio = 70
   MaxHeapSize      = 1447034880 (1380.0MB) //最大堆空間
   NewSize          = 1310720 (1.25MB)
   MaxNewSize       = 17592186044415 MB
   OldSize          = 5439488 (5.1875MB)
   NewRatio         = 2
   SurvivorRatio    = 8
   PermSize         = 21757952 (20.75MB)
   MaxPermSize      = 268435456 (256.0MB)
   G1HeapRegionSize = 0 (0.0MB)

Heap Usage:
PS Young Generation //年輕代
Eden Space:
   capacity = 387448832 (369.5MB)
   used     = 337520592 (321.8847198486328MB)
   free     = 49928240 (47.61528015136719MB)
   87.11359129868276% used
From Space:
   capacity = 47448064 (45.25MB)
   used     = 29189704 (27.83747100830078MB)
   free     = 18258360 (17.41252899169922MB)
   61.51927294652106% used
To Space:
   capacity = 47448064 (45.25MB)
   used     = 0 (0.0MB)
   free     = 47448064 (45.25MB)
   0.0% used
PS Old Generation //老年代
   capacity = 357957632 (341.375MB)
   used     = 217899800 (207.8054428100586MB)
   free     = 140057832 (133.5695571899414MB)
   60.873070028578134% used
PS Perm Generation //永久代
   capacity = 245891072 (234.5MB)
   used     = 122883168 (117.19052124023438MB)
   free     = 123007904 (117.30947875976562MB)
   49.974635923340884% used

39279 interned Strings occupying 3731248 bytes.

jmap -dump:live,format=b,file=F:/heap.bin pid:dump java heap in hprof binary format
匯出堆二進位制資訊

[email protected]>jmap -dump:live,format=b,file=heap.bin 29136
Dumping heap to heap.bin ...
Heap dump file created

我們可以用MemoryAnalyzer分析檔案，介面如下：


[img]http://dl2.iteye.com/upload/attachment/0123/2948/8c7de339-4cd9-316b-9301-b0b38132c9b0.png[/img]

具體如何分析我們就不說,網上很多相關文章

[email protected]>jps
42548 JConsole
30708 Jps
29136 Bootstrap
2692 org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar
37412


jmap -histo:live pid檢視堆中活動的物件以及大小 

[email protected]>jmap -histo:live 29136 > jmap-histo.txt



jmap-histo.txt的先關資訊：
 num     #instances         #bytes  class name
----------------------------------------------
   1:        104389       15407704  <constMethodKlass>
   2:        105675       14934912  [C
   3:        104389       13377904  <methodKlass>
   4:         29296       11657864  [B
   5:          8286       10644280  <constantPoolKlass>
   6:          6968        6312896  <constantPoolCacheKlass>
   7:          8286        6266968  <instanceKlassKlass>
   8:        102853        2468472  java.lang.String
   9:          3293        1912896  <methodDataKlass>
  10:          9804        1328400  [I
  11:         15433        1234640  java.lang.reflect.Method
  12:         27893         892576  java.util.concurrent.ConcurrentHashMap$HashEntry
  13:          9045         892056  java.lang.Class
  14:           108         852304  [J
  15:         12221         851448  [S
  16:         18896         755840  java.util.LinkedHashMap$Entry
  17:         13262         748464  [[I
  18:         12725         624784  [Ljava.lang.Object;
  19:          5072         580528  [Ljava.util.HashMap$Entry;
  20:         17520         560640  java.util.HashMap$Entry
  21:          7618         487552  java.net.URL
  22:           742         403648  <objArrayKlassKlass>
  23:         12033         385056  java.lang.ref.WeakReference
  24:         14549         349176  java.util.ArrayList
  25:          5488         307328  java.util.LinkedHashMap
  26:          2225         298408  [Ljava.util.concurrent.ConcurrentHashMap$HashEntry;
  27:          5571         267408  org.apache.catalina.loader.ResourceEntry
  28:          4921         236208  org.aspectj.weaver.reflect.ShadowMatchImpl
  29:          6530         208600  [Ljava.lang.String;
  30:         13015         208240  java.lang.Object
  31:          4923         196920  java.lang.ref.SoftReference
  32:          7706         164344  [Ljava.lang.Class;
  33:          5002         160064  java.util.Hashtable$Entry
  34:          4921         157472  org.aspectj.weaver.patterns.ExposedState
  35:          3236         155328  java.util.HashMap
  36:          5972         143328  java.beans.MethodRef
  37:          2034         113904  java.beans.MethodDescriptor
  38:          2334         112032  org.springframework.util.ConcurrentReferenceHashMap$SoftEntryReference
  39:          1010          96960  org.springframework.beans.GenericTypeAwarePropertyDescriptor
  40:          5285          94912  [Z
  41:          3938          94512  java.util.Collections$UnmodifiableRandomAccessList
  42:          1269          91368  java.lang.reflect.Constructor
  43:          2225          89000  java.util.concurrent.ConcurrentHashMap$Segment
  44:           981          86328  org.apache.ibatis.mapping.MappedStatement
  45:          2570          82240  java.util.LinkedList
  46:          2513          80416  java.util.concurrent.locks.ReentrantLock$NonfairSync
  47:          4921          78736  [Lorg.aspectj.weaver.ast.Var;
  48:          1025          73800  org.apache.jasper.compiler.Node$TemplateText
  49:           957          68904  java.beans.PropertyDescriptor
  50:           473          68112  org.aspectj.weaver.ReferenceType
  51:          1179          66024  org.apache.jasper.compiler.Mark
  52:           506          65504  [Ljava.util.Hashtable$Entry;
  53:           111          63288  [Ljava.util.WeakHashMap$Entry;
  54:          3734          59744  org.apache.ibatis.scripting.xmltags.TextSqlNode
  55:          1816          58112  com.kingbase.util.Oid
  56:          1441          57640  java.util.WeakHashMap$Entry
  57:           784          56448  java.lang.reflect.Field
  58:           940          52640  org.springframework.core.annotation.AnnotationAttributes
  59:           804          51456  com.kingbase.core.Field
  60:          1251          50040  org.apache.log4j.Logger
  61:          2027          48648  java.util.LinkedList$Node
  62:           304          48640  org.aspectj.weaver.BoundedReferenceType
  63:           598          46832  [Ljava.util.concurrent.ConcurrentHashMap$Segment;
  64:          1128          45120  java.util.TreeMap$Entry
  65:          1841          44184  org.springframework.cglib.core.Signature
  66:           898          43104  org.apache.tomcat.util.modeler.AttributeInfo
  67:          1201          38432  java.util.Stack
  68:          1559          37416  org.apache.log4j.CategoryKey
  69:          2324          37184  java.util.LinkedHashSet
  70:          2168          34688  java.util.HashMap$KeySet
  71:          2069          33104  org.apache.ibatis.scripting.xmltags.MixedSqlNode
  72:           687          32976  org.apache.tomcat.util.buf.ByteChunk
  73:           575          32200  java.lang.Package
  74:           639          30672  java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync
  75:           221          30624  [[C
  76:           195          29640  org.springframework.beans.factory.support.RootBeanDefinition
  77:           598          28704  java.util.concurrent.ConcurrentHashMap
  78:           137          28496  com.kingbase.jdbc4.Jdbc4Statement
  79:           885          28320  org.springframework.cglib.proxy.MethodProxy
  80:          1738          27808  java.util.Collections$UnmodifiableSet
  81:           863          27616  org.springframework.cglib.proxy.MethodProxy$CreateInfo
  82:           143          27456  com.kingbase.jdbc4.Jdbc4ResultSet
  83:            13          26832  [Lorg.apache.ibatis.ognl.OgnlRuntime$ClassCache$Entry;
  84:           552          26496  org.apache.tomcat.util.buf.MessageBytes
  85:           222          26448  [Ljava.beans.MethodDescriptor;
  86:          1074          25776  org.slf4j.impl.Log4jLoggerAdapter
  87:           447          25032  org.apache.ibatis.mapping.ResultMap
  88:           602          24080  org.apache.tomcat.util.buf.CharChunk
  89:           981          23544  org.apache.ibatis.scripting.xmltags.DynamicSqlSource
  90:           981          23544  org.apache.ibatis.mapping.ParameterMap
  91:          1461          23376  java.util.HashSet
  92:           724          23168  javax.management.MBeanAttributeInfo
  93:           964          23136  org.apache.ibatis.scripting.xmltags.IfSqlNode
  94:           453          21744  java.util.Hashtable
...
...n
416:             1             16  org.springframework.aop.support.annotation.AnnotationMethodMatcher
3417:             1             16  java.util.ResourceBundle$Control
3418:             1             16  sun.reflect.GeneratedMethodAccessor38
3419:             1             16  [Lcom.sun.org.apache.xerces.internal.impl.xs.SubstitutionGroupHandler$OneSubGroup;
3420:             1             16  sun.nio.ch.Util$1
3421:             1             16  org.springframework.web.servlet.FrameworkServlet$ContextRefreshListener
3422:             1             16  org.apache.ibatis.ognl.ObjectPropertyAccessor
3423:             1             16  sun.reflect.GeneratedMethodAccessor8
3424:             1             16  com.sun.org.apache.xerces.internal.impl.dv.xs.IntegerDV
3425:             1             16  sun.reflect.GeneratedMethodAccessor30
3426:             1             16  org.springframework.beans.factory.parsing.FailFastProblemReporter
3427:             1             16  org.aspectj.util.FuzzyBoolean$NeverFuzzyBoolean
3428:             1             16  org.apache.catalina.connector.Request$5
3429:             1             16  org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration$1
3430:             1             16  com.fh.cachedb.CodeTableHolder
3431:             1             16  sun.reflect.GeneratedConstructorAccessor47
3432:             1             16  java.lang.String$CaseInsensitiveComparator
3433:             1             16  sun.reflect.GeneratedConstructorAccessor42
3434:             1             16  sun.reflect.GeneratedConstructorAccessor38
Total        946918      105239816



[email protected]>jps
42548 JConsole
30708 Jps
29136 Bootstrap
2692 org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar
37412


jstack pid ：檢視jvm執行緒執行狀態，是否有死鎖現象等等資訊)

[email protected]>jstack 29136 > jstack.txt

jstack.txt先關內容：
2017-02-23 18:44:50
Full thread dump Java HotSpot(TM) 64-Bit Server VM (24.79-b02 mixed mode):

"Attach Listener" daemon prio=10 tid=0x0000000000705800 nid=0x5e66 runnable [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
//執行緒池中的執行緒3正在執行
"pool-2-thread-3" prio=10 tid=0x0000000000867800 nid=0x5e04 runnable [0x00007fce9710f000]
   java.lang.Thread.State: RUNNABLE
	at java.util.HashMap.createEntry(HashMap.java:897)
	at java.util.HashMap.addEntry(HashMap.java:884)
	at java.util.HashMap.put(HashMap.java:505)
	at com.fh.util.PageData.put(PageData.java:73)
	at com.fh.util.network.SqlTypeUtil.getCityData(SqlTypeUtil.java:37)
	at com.fh.thread.CityDataToUpdateCallble.call(CityDataToUpdateCallble.java:109)
	at com.fh.thread.CityDataToUpdateCallble.call(CityDataToUpdateCallble.java:1)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:745)
//執行緒池中執行緒2，正在執行，在等待waiting on condition  [0x00007fce97210000]
"pool-2-thread-2" prio=10 tid=0x0000000000855000 nid=0x5e01 waiting on condition [0x00007fce97210000]
   java.lang.Thread.State: RUNNABLE
	at com.fh.util.network.SqlTypeUtil.getCityData(SqlTypeUtil.java:35)
	at com.fh.thread.CityDataToUpdateCallble.call(CityDataToUpdateCallble.java:109)
	at com.fh.thread.CityDataToUpdateCallble.call(CityDataToUpdateCallble.java:1)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:745)
//tomcat bio 執行緒處於等待狀態waiting on condition [0x00007fce960f1000]
"http-bio-8080-exec-10" daemon prio=10 tid=0x0000000000713000 nid=0x5dff waiting on condition [0x00007fce960f1000]
   java.lang.Thread.State: WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- parking to wait for  <0x00000000c71fe5e8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
	at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2043)
	at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
	at org.apache.tomcat.util.threads.TaskQueue.take(TaskQueue.java:104)
	at org.apache.tomcat.util.threads.TaskQueue.take(TaskQueue.java:32)
	at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1068)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:745)
	...
"http-bio-8080-exec-1" daemon prio=10 tid=0x0000000000997800 nid=0x5df5 waiting on condition [0x00007fce9e05c000]
   java.lang.Thread.State: WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- parking to wait for  <0x00000000c71fe5e8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
	at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2043)
	at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
	at org.apache.tomcat.util.threads.TaskQueue.take(TaskQueue.java:104)
	at org.apache.tomcat.util.threads.TaskQueue.take(TaskQueue.java:32)
	at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1068)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:745)
//執行緒Java2D Disposer處於等待狀態：in Object.wait() [0x00007fce976b9000]
	"Java2D Disposer" daemon prio=10 tid=0x0000000000e0f000 nid=0x5df8 in Object.wait() [0x00007fce976b9000]
   java.lang.Thread.State: WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c758fa40> (a java.lang.ref.ReferenceQueue$Lock)
	at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:135)
	- locked <0x00000000c758fa40> (a java.lang.ref.ReferenceQueue$Lock)
	at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:151)
	at sun.java2d.Disposer.run(Disposer.java:145)
	at java.lang.Thread.run(Thread.java:745)

	"ajp-bio-8009-Acceptor-0" daemon prio=10 tid=0x00007fce904a8000 nid=0x5df3 runnable [0x00007fce9c162000]
   java.lang.Thread.State: RUNNABLE
	at java.net.PlainSocketImpl.socketAccept(Native Method)
	at java.net.AbstractPlainSocketImpl.accept(AbstractPlainSocketImpl.java:398)
	at java.net.ServerSocket.implAccept(ServerSocket.java:530)
	at java.net.ServerSocket.accept(ServerSocket.java:498)
	at org.apache.tomcat.util.net.DefaultServerSocketFactory.acceptSocket(DefaultServerSocketFactory.java:60)
	at org.apache.tomcat.util.net.JIoEndpoint$Acceptor.run(JIoEndpoint.java:222)
	at java.lang.Thread.run(Thread.java:745)
//處於睡眠狀態
"http-bio-8080-AsyncTimeout" daemon prio=10 tid=0x00007fce90793000 nid=0x5df2 sleeping[0x00007fce9dc58000]
   java.lang.Thread.State: TIMED_WAITING (sleeping)
	at java.lang.Thread.sleep(Native Method)
	at org.apache.tomcat.util.net.JIoEndpoint$AsyncTimeout.run(JIoEndpoint.java:152)
	at java.lang.Thread.run(Thread.java:745)

"http-bio-8080-Acceptor-0" daemon prio=10 tid=0x0000000000810000 nid=0x5df1 runnable [0x00007fce9dd59000]
   java.lang.Thread.State: RUNNABLE
	at java.net.PlainSocketImpl.socketAccept(Native Method)
	at java.net.AbstractPlainSocketImpl.accept(AbstractPlainSocketImpl.java:398)
	at java.net.ServerSocket.implAccept(ServerSocket.java:530)
	at java.net.ServerSocket.accept(ServerSocket.java:498)
	at org.apache.tomcat.util.net.DefaultServerSocketFactory.acceptSocket(DefaultServerSocketFactory.java:60)
	at org.apache.tomcat.util.net.JIoEndpoint$Acceptor.run(JIoEndpoint.java:222)
	at java.lang.Thread.run(Thread.java:745)

"ContainerBackgroundProcessor[StandardEngine[Catalina]]" daemon prio=10 tid=0x0000000001ec3800 nid=0x5df0 runnable [0x00007fce9de5a000]
   java.lang.Thread.State: RUNNABLE
	at java.io.UnixFileSystem.getBooleanAttributes0(Native Method)
	at java.io.UnixFileSystem.getBooleanAttributes(UnixFileSystem.java:242)
	at java.io.File.isDirectory(File.java:843)
	at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:1151)
	at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:497)
	at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1757)
	at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:333)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
	at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
	at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1370)
	at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1542)
	at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1552)
	at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1520)
	at java.lang.Thread.run(Thread.java:745)
//Druid執行緒池處理睡眠，等待waiting on condition [0x00007fce9c263000]
"Druid-ConnectionPool-Destroy-1086652952" daemon prio=10 tid=0x00007fce904ef800 nid=0x5def waiting on condition [0x00007fce9c263000]
   java.lang.Thread.State: TIMED_WAITING (sleeping)
	at java.lang.Thread.sleep(Native Method)
	at com.alibaba.druid.pool.DruidDataSource$DestroyConnectionThread.run(DruidDataSource.java:1898)

"Druid-ConnectionPool-Create-1086652952" daemon prio=10 tid=0x00007fce90015800 nid=0x5dee waiting on condition [0x00007fce9c364000]
   java.lang.Thread.State: WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- parking to wait for  <0x00000000c633d178> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
	at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2043)
	at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:1824)


"%0055ser%0058%004dapper.data" prio=10 tid=0x00007fce904cf800 nid=0x5dec waiting on condition [0x00007fce9c882000]
   java.lang.Thread.State: TIMED_WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- parking to wait for  <0x00000000c6196fe8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
	at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:226)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2082)
	at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1090)
	at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:807)
	at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1068)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:745)

"[email protected]" daemon prio=10 tid=0x00007fce904bf800 nid=0x5dea in Object.wait() [0x00007fce9c983000]
   java.lang.Thread.State: WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c61bed80> (a java.util.TaskQueue)
	at java.lang.Object.wait(Object.java:503)
	at java.util.TimerThread.mainLoop(Timer.java:526)
	- locked <0x00000000c61bed80> (a java.util.TaskQueue)
	at java.util.TimerThread.run(Timer.java:505)

"Druid-ConnectionPool-Destroy-1795695054" daemon prio=10 tid=0x00007fce904b7000 nid=0x5de9 waiting on condition [0x00007fce9ccc2000]
   java.lang.Thread.State: TIMED_WAITING (sleeping)
	at java.lang.Thread.sleep(Native Method)
	at com.alibaba.druid.pool.DruidDataSource$DestroyConnectionThread.run(DruidDataSource.java:1898)

"Druid-ConnectionPool-Create-1795695054" daemon prio=10 tid=0x00007fce90537800 nid=0x5de8 waiting on condition [0x00007fce9cdc3000]
   java.lang.Thread.State: WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- parking to wait for  <0x00000000c627f1d0> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
	at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2043)
	at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:1824)

"Abandoned connection cleanup thread" daemon prio=10 tid=0x00007fce90419000 nid=0x5de6 in Object.wait() [0x00007fce9cec4000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627f208> (a java.lang.ref.ReferenceQueue$Lock)
	at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:135)
	- locked <0x00000000c627f208> (a java.lang.ref.ReferenceQueue$Lock)
	at com.mysql.jdbc.AbandonedConnectionCleanupThread.run(AbandonedConnectionCleanupThread.java:43)

"Timer-0" daemon prio=10 tid=0x00007fce90351800 nid=0x5de5 in Object.wait() [0x00007fce9cfc5000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627f2a8> (a java.util.TaskQueue)
	at java.util.TimerThread.mainLoop(Timer.java:552)
	- locked <0x00000000c627f2a8> (a java.util.TaskQueue)
	at java.util.TimerThread.run(Timer.java:505)
//定時任務排程執行緒，初始化10個執行緒，
"schedulerFactoryBean_QuartzSchedulerThread" prio=10 tid=0x00007fce9034c000 nid=0x5de4 runnable [0x00007fce9d0c6000]
   java.lang.Thread.State: RUNNABLE
	at org.quartz.utils.Key.compareTo(Key.java:152)
	at org.quartz.Trigger$TriggerTimeComparator.compare(Trigger.java:321)
	at org.quartz.Trigger$TriggerTimeComparator.compare(Trigger.java:326)
	at org.quartz.simpl.TriggerWrapperComparator.compare(RAMJobStore.java:1705)
	at org.quartz.simpl.TriggerWrapperComparator.compare(RAMJobStore.java:1698)
	at java.util.TreeMap.getEntryUsingComparator(TreeMap.java:369)
	at java.util.TreeMap.getEntry(TreeMap.java:340)
	at java.util.TreeMap.remove(TreeMap.java:595)
	at java.util.TreeSet.remove(TreeSet.java:276)
	at org.quartz.simpl.RAMJobStore.acquireNextTriggers(RAMJobStore.java:1403)
	- locked <0x00000000c62cd9e8> (a java.lang.Object)
	at org.quartz.core.QuartzSchedulerThread.run(QuartzSchedulerThread.java:272)
//RUNNABLE
"schedulerFactoryBean_Worker-10" prio=10 tid=0x00007fce90348000 nid=0x5de3 runnable [0x00007fce9d1c7000]
   java.lang.Thread.State: RUNNABLE
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627f420> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c627f420> (a java.lang.Object)
//TIMED_WAITING
"schedulerFactoryBean_Worker-9" prio=10 tid=0x00007fce90346800 nid=0x5de2 in Object.wait() [0x00007fce9d2c8000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627f4b0> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c627f4b0> (a java.lang.Object)
//RUNNABLE
"schedulerFactoryBean_Worker-8" prio=10 tid=0x00007fce90335800 nid=0x5de1 runnable [0x00007fce9d3c9000]
   java.lang.Thread.State: RUNNABLE
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627f540> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c627f540> (a java.lang.Object)
//TIMED_WAITING
"schedulerFactoryBean_Worker-7" prio=10 tid=0x00007fce90333800 nid=0x5de0 in Object.wait() [0x00007fce9d4ca000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627f5d0> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c627f5d0> (a java.lang.Object)
//TIMED_WAITING
"schedulerFactoryBean_Worker-6" prio=10 tid=0x00007fce90331800 nid=0x5ddf in Object.wait() [0x00007fce9d5cb000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627f660> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c627f660> (a java.lang.Object)
//TIMED_WAITING
"schedulerFactoryBean_Worker-5" prio=10 tid=0x00007fce90330000 nid=0x5dde in Object.wait() [0x00007fce9d6cc000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c62804c0> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c62804c0> (a java.lang.Object)
//TIMED_WAITING
"schedulerFactoryBean_Worker-4" prio=10 tid=0x00007fce9032e000 nid=0x5ddd in Object.wait() [0x00007fce9d7cd000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c62802f0> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c62802f0> (a java.lang.Object)
//TIMED_WAITING
"schedulerFactoryBean_Worker-3" prio=10 tid=0x00007fce9032c800 nid=0x5ddc in Object.wait() [0x00007fce9d8ce000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c6280120> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c6280120> (a java.lang.Object)
//TIMED_WAITING
"schedulerFactoryBean_Worker-2" prio=10 tid=0x00007fce9032b000 nid=0x5ddb in Object.wait() [0x00007fce9d9cf000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627ff50> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c627ff50> (a java.lang.Object)
//RUNNABLE
"schedulerFactoryBean_Worker-1" prio=10 tid=0x00007fce90327000 nid=0x5dda runnable [0x00007fce9dad0000]
   java.lang.Thread.State: RUNNABLE
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c627fd80> (a java.lang.Object)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:568)
	- locked <0x00000000c627fd80> (a java.lang.Object)

//GC
"GC Daemon" daemon prio=10 tid=0x00000000008a1000 nid=0x5dd7 in Object.wait() [0x00007fce9e5f6000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c5628bf0> (a sun.misc.GC$LatencyLock)
	at sun.misc.GC$Daemon.run(GC.java:117)
	- locked <0x00000000c5628bf0> (a sun.misc.GC$LatencyLock)

"Service Thread" daemon prio=10 tid=0x00007fce98035800 nid=0x5dd5 runnable [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
//編譯執行緒
"C2 CompilerThread1" daemon prio=10 tid=0x00007fce98033000 nid=0x5dd4 waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"C2 CompilerThread0" daemon prio=10 tid=0x00007fce98030000 nid=0x5dd3 waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Signal Dispatcher" daemon prio=10 tid=0x00007fce9802d800 nid=0x5dd2 runnable [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Finalizer" daemon prio=10 tid=0x00007fce98001000 nid=0x5dd1 in Object.wait() [0x00007fce9f41e000]
   java.lang.Thread.State: WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c5842558> (a java.lang.ref.ReferenceQueue$Lock)
	at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:135)
	- locked <0x00000000c5842558> (a java.lang.ref.ReferenceQueue$Lock)
	at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:151)
	at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:209)

"Reference Handler" daemon prio=10 tid=0x0000000000677800 nid=0x5dd0 in Object.wait() [0x00007fce9f51f000]
   java.lang.Thread.State: WAITING (on object monitor)
	at java.lang.Object.wait(Native Method)
	- waiting on <0x00000000c56a9438> (a java.lang.ref.Reference$Lock)
	at java.lang.Object.wait(Object.java:503)
	at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:133)
	- locked <0x00000000c56a9438> (a java.lang.ref.Reference$Lock)
//主執行緒
"main" prio=10 tid=0x000000000060a800 nid=0x5dc6 runnable [0x00007fcea9817000]
   java.lang.Thread.State: RUNNABLE
	at java.net.PlainSocketImpl.socketAccept(Native Method)
	at java.net.AbstractPlainSocketImpl.accept(AbstractPlainSocketImpl.java:398)
	at java.net.ServerSocket.implAccept(ServerSocket.java:530)
	at java.net.ServerSocket.accept(ServerSocket.java:498)
	at org.apache.catalina.core.StandardServer.await(StandardServer.java:470)
	at org.apache.catalina.startup.Catalina.await(Catalina.java:781)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:727)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:294)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:428)
//虛擬機器執行緒
"VM Thread" prio=10 tid=0x0000000000673000 nid=0x5dcf runnable 
//GC任務執行緒
"GC task thread#0 (ParallelGC)" prio=10 tid=0x0000000000620800 nid=0x5dc7 runnable 

"GC task thread#1 (ParallelGC)" prio=10 tid=0x0000000000622800 nid=0x5dc8 runnable 

"GC task thread#2 (ParallelGC)" prio=10 tid=0x0000000000624000 nid=0x5dc9 runnable 

"GC task thread#3 (ParallelGC)" prio=10 tid=0x0000000000626000 nid=0x5dca runnable 

"GC task thread#4 (ParallelGC)" prio=10 tid=0x0000000000628000 nid=0x5dcb runnable 

"GC task thread#5 (ParallelGC)" prio=10 tid=0x0000000000629800 nid=0x5dcc runnable 

"GC task thread#6 (ParallelGC)" prio=10 tid=0x000000000062b800 nid=0x5dcd runnable 

"GC task thread#7 (ParallelGC)" prio=10 tid=0x000000000062d800 nid=0x5dce runnable 

"VM Periodic Task Thread" prio=10 tid=0x00007fce98040800 nid=0x5dd6 waiting on condition 

JNI global references: 478



jstat -gc pid:可以顯示gc的資訊，檢視gc的次數，及時間。

[email protected]>jstat -gc 29136
 S0C    S1C    S0U    S1U      EC       EU        OC         OU       PC     PU    YGC     YGCT    FGC    FGCT     GCT
4288.0 4288.0 1639.1  0.0   34688.0  33781.3   86336.0    45491.6   83968.0 59198.3     96    0.521   6      0.714    1.235

其中最後五項，分別是young gc的次數，young gc的時間，full gc的次數，full gc的時間，gc的總時間。

jstat -util pid:統計gc資訊統計與-gc合用。

jstat -gcutil PID 1000（重新整理頻率） 3（次數）:檢視jvm的gc情況和記憶體使用情況

[email protected]> jstat -gcutil 29136 1000 3
  S0     S1     E      O      P     YGC     YGCT    FGC    FGCT     GCT
  0.00  35.42  55.86  50.93  70.10     87    0.491     6    0.714    1.205
  0.00  35.42  57.56  50.93  70.10     87    0.491     6    0.714    1.205
  0.00  35.42  58.04  50.93  70.10     87    0.491     6    0.714    1.205


S0：Heap上的 Survivor space 0 段已使用空間的百分比
S1：Heap上的 Survivor space 1 段已使用空間的百分比
E： Heap上的 Eden space 段已使用空間的百分比
O：Heap上的 Old space 段已使用空間的百分比
P： Perm space 已使用空間的百分比
YGC：從程式啟動到取樣時發生Young GC的次數
YGCT：Young GC所用的時間(單位秒)
FGC：從程式啟動到取樣時發生Full GC的次數
FGCT：Full GC所用的時間(單位秒)
GCT：用於垃圾回收的總時間(單位秒)


jstat -class pid:顯示載入class的數量，及所佔空間等資訊

[email protected]>jstat -class 29136
Loaded  Bytes  Unloaded  Bytes     Time
  8735 18805.4       85   137.6       7.86



jstat -compiler pid:顯示VM實時編譯的數量等資訊。 

[email protected]>jstat -compiler 29136
Compiled Failed Invalid   Time   FailedType FailedMethod
    2093      1       0    24.51          1 org/apache/catalina/loader/WebappClassLoaderBase findResourceInternal



jstat -gccapacity pid:可以顯示，VM記憶體中三代（young,old,perm）物件的使用和佔用大小，

[email protected]>jstat -gccapacity 29136
 NGCMN    NGCMX     NGC     S0C   S1C       EC      OGCMN      OGCMX       OGC         OC      PGCMN    PGCMX     PGC       PC     YGC    FGC

 43136.0 340736.0  43264.0 4288.0 4288.0  34688.0    86336.0  1731840.0    86336.0    86336.0  21248.0  83968.0  83968.0  83968.0     98     6


如：PGCMN顯示的是最小perm的記憶體使用量，PGCMX顯示的是perm的記憶體最大使用量，
PGC是當前新生成的perm記憶體佔用量，PC是但前perm記憶體佔用量。其他的可以根據這個類推， OC是old內純的佔用量。

jstat -gcnew pid:new物件的資訊。 

[email protected]>jstat -gcnew 29136
 S0C    S1C    S0U    S1U   TT MTT  DSS      EC       EU     YGC     YGCT
4288.0 4288.0    0.0 3512.2  6   6 2144.0  34688.0  28683.1    101    0.553



jstat -gcnewcapacity pid:new物件的資訊及其佔用量。 

[email protected]>jstat -gcnewcapacity 29136
  NGCMN      NGCMX       NGC      S0CMX     S0C     S1CMX     S1C       ECMX        EC      YGC   FGC
   43136.0   340736.0    43264.0  34048.0   4288.0  34048.0   4288.0   272640.0    34688.0   102     6


jstat -gcold pid:old物件的資訊。 

[email protected]>jstat -gcold 29136
   PC       PU        OC          OU       YGC    FGC    FGCT     GCT
 83968.0  59291.3     86336.0     50136.9    102     6    0.714    1.270


jstat -gcoldcapacity pid:old物件的資訊及其佔用量。 


[email protected]>jstat -gcoldcapacity 29136
   OGCMN       OGCMX        OGC         OC       YGC   FGC    FGCT     GCT
    86336.0   1731840.0     86336.0     86336.0   102     6    0.714    1.270



jstat -gcpermcapacity pid: perm物件的資訊及其佔用量。



[email protected]>jstat -gcpermcapacity 29136
  PGCMN      PGCMX       PGC         PC      YGC   FGC    FGCT     GCT
   21248.0    83968.0    83968.0    83968.0   103     6    0.714    1.272





jstat -printcompilation pid:當前VM執行的資訊


[email protected]>jstat -printcompilation 29136
Compiled  Size  Type Method
    2162    141    1 com/kingbase/core/KB_Stream_Tcpip Receive



檢視虛擬機器狀態用到的幾個重要命令
jps
jinfo -flags 2692
jmap -heap 2692
jmap -dump:live,format=b,file=heap.bin 29136
jmap -histo:live 29136 > jmap-histo.txt
jstack 29136 > jstack.txt
jstat -gcutil 29136 1000 3
問題：
[color=red]1.Attaching to process ID 60064, please wait...
Error attaching to process: Windbg Error: ReadVirtual failed!

2.60064: Unable to attach to 32-bit process running under WOW64
The -F option can be used when the target process is not responding[/color]
當出現以上問題時：首先看JDK版本、位數，再看執行緒許可權。

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