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最新评论
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Donald_Draper:
Donald_Draper 写道刘落落cici 写道能给我发一 ...
DatagramChannelImpl 解析三(多播) -
Donald_Draper:
刘落落cici 写道能给我发一份这个类的源码吗Datagram ...
DatagramChannelImpl 解析三(多播) -
lyfyouyun:
请问楼主,执行消息发送的时候,报错:Transport sch ...
ActiveMQ连接工厂、连接详解 -
ezlhq:
关于 PollArrayWrapper 状态含义猜测:参考 S ...
WindowsSelectorImpl解析一(FdMap,PollArrayWrapper) -
flyfeifei66:
打算使用xmemcache作为memcache的客户端,由于x ...
Memcached分布式客户端(Xmemcached)
关于cmd命令的重定向输出 :http://blog.csdn.net/jw72jw/article/details/7404255
jstack和线程dump分析:http://jameswxx.iteye.com/blog/1041173
Java自带的性能监测工具用法简介:http://blog.csdn.net/feihong247/article/details/7874063
linux下查看虚拟机的状态:http://blog.sina.com.cn/s/blog_472b9eb20100nhy5.html
JVM:查看java内存情况命令:http://www.cnblogs.com/zzck/archive/2016/07/26/5707168.html
查看JAVA状态的命令主要有一下几种,jps,jinfo,jmap,jstack,jstat,jconsole,jVisualVM;
jconsole,jVisualVM是界面化的工具,这里们就不讲了,用用就知道,注意与JDK的版本问题;下面我们来看以下几个命令jps(查看java进程),jinfo(查看JVM启动参数),jmap(查看堆内存状态),jstack(查看JVM线程运行状态),jstat(查看虚拟机垃圾回收状态)。
jps:查看Java进程
jinfo -flags:查看java进程参数参数
jmap -heap:查看堆状况
jmap -dump:live,format=b,file=F:/heap.bin pid:dump java heap in hprof binary format
导出堆二进制信息
我们可以用MemoryAnalyzer分析文件,界面如下:
具体如何分析我们就不说,网上很多相关文章
jmap -histo:live pid查看堆中活动的对象以及大小
jmap-histo.txt的先关信息:
jstack pid :查看jvm线程运行状态,是否有死锁现象等等信息)
jstack.txt先关内容:
jstat -gc pid:可以显示gc的信息,查看gc的次数,及时间。
其中最后五项,分别是young gc的次数,young gc的时间,full gc的次数,full gc的时间,gc的总时间。
jstat -util pid:统计gc信息统计与-gc合用。
jstat -gcutil PID 1000(刷新频率) 3(次数):查看jvm的gc情况和内存使用情况
S0:Heap上的 Survivor space 0 段已使用空间的百分比
S1:Heap上的 Survivor space 1 段已使用空间的百分比
E: Heap上的 Eden space 段已使用空间的百分比
O:Heap上的 Old space 段已使用空间的百分比
P: Perm space 已使用空间的百分比
YGC:从程序启动到采样时发生Young GC的次数
YGCT:Young GC所用的时间(单位秒)
FGC:从程序启动到采样时发生Full GC的次数
FGCT:Full GC所用的时间(单位秒)
GCT:用于垃圾回收的总时间(单位秒)
jstat -class pid:显示加载class的数量,及所占空间等信息
jstat -compiler pid:显示VM实时编译的数量等信息。
jstat -gccapacity pid:可以显示,VM内存中三代(young,old,perm)对象的使用和占用大小,
如:PGCMN显示的是最小perm的内存使用量,PGCMX显示的是perm的内存最大使用量,
PGC是当前新生成的perm内存占用量,PC是但前perm内存占用量。其他的可以根据这个类推, OC是old内纯的占用量。
jstat -gcnew pid:new对象的信息。
jstat -gcnewcapacity pid:new对象的信息及其占用量。
jstat -gcold pid:old对象的信息。
jstat -gcoldcapacity pid:old对象的信息及其占用量。
jstat -gcpermcapacity pid: perm对象的信息及其占用量。
jstat -printcompilation pid:当前VM执行的信息
查看虚拟机状态用到的几个重要命令
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
问题:
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
当出现以上问题时:首先看JDK版本、位数,再看线程权限。
jstack和线程dump分析:http://jameswxx.iteye.com/blog/1041173
Java自带的性能监测工具用法简介:http://blog.csdn.net/feihong247/article/details/7874063
linux下查看虚拟机的状态:http://blog.sina.com.cn/s/blog_472b9eb20100nhy5.html
JVM:查看java内存情况命令:http://www.cnblogs.com/zzck/archive/2016/07/26/5707168.html
查看JAVA状态的命令主要有一下几种,jps,jinfo,jmap,jstack,jstat,jconsole,jVisualVM;
jconsole,jVisualVM是界面化的工具,这里们就不讲了,用用就知道,注意与JDK的版本问题;下面我们来看以下几个命令jps(查看java进程),jinfo(查看JVM启动参数),jmap(查看堆内存状态),jstack(查看JVM线程运行状态),jstat(查看虚拟机垃圾回收状态)。
jps:查看Java进程
Donald_Draper@Centos7>jps 42548 JConsole 10868 Jps 29136 Bootstrap 2692 org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar 37412
jinfo -flags:查看java进程参数参数
Donald_Draper@Centos7>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:查看堆状况
Donald_Draper@Centos7>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) //最大堆空间 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 //年轻代 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
导出堆二进制信息
Donald_Draper@Centos7>jmap -dump:live,format=b,file=heap.bin 29136 Dumping heap to heap.bin ... Heap dump file created
我们可以用MemoryAnalyzer分析文件,界面如下:
具体如何分析我们就不说,网上很多相关文章
Donald_Draper@Centos7>jps 42548 JConsole 30708 Jps 29136 Bootstrap 2692 org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar 37412
jmap -histo:live pid查看堆中活动的对象以及大小
Donald_Draper@Centos7>jmap -histo:live 29136 > jmap-histo.txt
jmap-histo.txt的先关信息:
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
Donald_Draper@Centos7>jps 42548 JConsole 30708 Jps 29136 Bootstrap 2692 org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar 37412
jstack pid :查看jvm线程运行状态,是否有死锁现象等等信息)
Donald_Draper@Centos7>jstack 29136 > jstack.txt
jstack.txt先关内容:
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 //线程池中的线程3正在运行 "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$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) //线程池中线程2,正在运行,在等待waiting on condition [0x00007fce97210000] "pool-2-thread-2" prio=10 tid=0x0000000000855000 nid=0x5e01 waiting on condition [0x00007fce97210000] java.lang.Thread.State: RUNNABLE at com.fh.util.network.SqlTypeUtil.getCityData(SqlTypeUtil.java:35) at com.fh.thread.CityDataToUpdateCallble.call(CityDataToUpdateCallble.java:109) at com.fh.thread.CityDataToUpdateCallble.call(CityDataToUpdateCallble.java:1) at java.util.concurrent.FutureTask.run(FutureTask.java:262) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) //tomcat bio 线程处于等待状态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) //线程Java2D Disposer处于等待状态: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$Acceptor.run(JIoEndpoint.java:222) at java.lang.Thread.run(Thread.java:745) //处于睡眠状态 "http-bio-8080-AsyncTimeout" daemon prio=10 tid=0x00007fce90793000 nid=0x5df2 sleeping[0x00007fce9dc58000] java.lang.Thread.State: TIMED_WAITING (sleeping) at java.lang.Thread.sleep(Native Method) at org.apache.tomcat.util.net.JIoEndpoint$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线程池处理睡眠,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$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) "net.sf.ehcache.CacheManager@1c2ae2cd" daemon prio=10 tid=0x00007fce904bf800 nid=0x5dea in Object.wait() [0x00007fce9c983000] java.lang.Thread.State: WAITING (on object monitor) at java.lang.Object.wait(Native Method) - waiting on <0x00000000c61bed80> (a java.util.TaskQueue) at java.lang.Object.wait(Object.java:503) at java.util.TimerThread.mainLoop(Timer.java:526) - locked <0x00000000c61bed80> (a java.util.TaskQueue) at java.util.TimerThread.run(Timer.java:505) "Druid-ConnectionPool-Destroy-1795695054" daemon prio=10 tid=0x00007fce904b7000 nid=0x5de9 waiting on condition [0x00007fce9ccc2000] java.lang.Thread.State: TIMED_WAITING (sleeping) at java.lang.Thread.sleep(Native Method) at com.alibaba.druid.pool.DruidDataSource$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$Lock) at com.mysql.jdbc.AbandonedConnectionCleanupThread.run(AbandonedConnectionCleanupThread.java:43) "Timer-0" daemon prio=10 tid=0x00007fce90351800 nid=0x5de5 in Object.wait() [0x00007fce9cfc5000] java.lang.Thread.State: TIMED_WAITING (on object monitor) at java.lang.Object.wait(Native Method) - waiting on <0x00000000c627f2a8> (a java.util.TaskQueue) at java.util.TimerThread.mainLoop(Timer.java:552) - locked <0x00000000c627f2a8> (a java.util.TaskQueue) at java.util.TimerThread.run(Timer.java:505) //定时任务调度线程,初始化10个线程, "schedulerFactoryBean_QuartzSchedulerThread" prio=10 tid=0x00007fce9034c000 nid=0x5de4 runnable [0x00007fce9d0c6000] java.lang.Thread.State: RUNNABLE at org.quartz.utils.Key.compareTo(Key.java:152) at org.quartz.Trigger$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 //编译线程 "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) //主线程 "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) //虚拟机线程 "VM Thread" prio=10 tid=0x0000000000673000 nid=0x5dcf runnable //GC任务线程 "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:可以显示gc的信息,查看gc的次数,及时间。
Donald_Draper@Centos7>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
其中最后五项,分别是young gc的次数,young gc的时间,full gc的次数,full gc的时间,gc的总时间。
jstat -util pid:统计gc信息统计与-gc合用。
jstat -gcutil PID 1000(刷新频率) 3(次数):查看jvm的gc情况和内存使用情况
Donald_Draper@Centos7> 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 段已使用空间的百分比
S1:Heap上的 Survivor space 1 段已使用空间的百分比
E: Heap上的 Eden space 段已使用空间的百分比
O:Heap上的 Old space 段已使用空间的百分比
P: Perm space 已使用空间的百分比
YGC:从程序启动到采样时发生Young GC的次数
YGCT:Young GC所用的时间(单位秒)
FGC:从程序启动到采样时发生Full GC的次数
FGCT:Full GC所用的时间(单位秒)
GCT:用于垃圾回收的总时间(单位秒)
jstat -class pid:显示加载class的数量,及所占空间等信息
Donald_Draper@Centos7>jstat -class 29136 Loaded Bytes Unloaded Bytes Time 8735 18805.4 85 137.6 7.86
jstat -compiler pid:显示VM实时编译的数量等信息。
Donald_Draper@Centos7>jstat -compiler 29136 Compiled Failed Invalid Time FailedType FailedMethod 2093 1 0 24.51 1 org/apache/catalina/loader/WebappClassLoaderBase findResourceInternal
jstat -gccapacity pid:可以显示,VM内存中三代(young,old,perm)对象的使用和占用大小,
Donald_Draper@Centos7>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显示的是最小perm的内存使用量,PGCMX显示的是perm的内存最大使用量,
PGC是当前新生成的perm内存占用量,PC是但前perm内存占用量。其他的可以根据这个类推, OC是old内纯的占用量。
jstat -gcnew pid:new对象的信息。
Donald_Draper@Centos7>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对象的信息及其占用量。
Donald_Draper@Centos7>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对象的信息。
Donald_Draper@Centos7>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对象的信息及其占用量。
Donald_Draper@Centos7>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对象的信息及其占用量。
Donald_Draper@Centos7>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:当前VM执行的信息
Donald_Draper@Centos7>jstat -printcompilation 29136 Compiled Size Type Method 2162 141 1 com/kingbase/core/KB_Stream_Tcpip Receive
查看虚拟机状态用到的几个重要命令
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
问题:
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
当出现以上问题时:首先看JDK版本、位数,再看线程权限。
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Java动态代理
2016-12-01 10:49 555深入浅析Spring 的aop实现原理:http://www. ... -
Java Stack用法
2016-10-13 09:58 1599java.util.Stack类简介 :http://blog ... -
JVM,ConcurrentMarkSweep垃圾回收器实战分析
2016-10-11 18:37 1664堆内存设置:http://blog.csdn.net/sivy ... -
深入理解Collections的unmodifiableMap(Map map)方法
2016-09-23 08:40 5075深刻理解IdentityHashMap:http://dona ... -
深刻理解IdentityHashMap
2016-09-22 16:34 2365新建POJO package test; public ...
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