# 1、查看当前系统运行的 java 程序(简略)
jps -l
632
6328 sun.tools.jps.Jps
# 2、查看当前系统运行的 java 程序(详细)
jps -lmvV
632 -Dosgi.requiredJavaVersion=1.8 [email protected]/eclipse-workspace -XX:+UseG1GC -XX:+UseStringDeduplication -XstartOnFirstThread -Dorg.eclipse.swt.internal.carbon.smallFonts -Dosgi.requiredJavaVersion=1.8 -Xms256m -Xmx1024m -Xdock:icon=../Resources/Eclipse.icns -XstartOnFirstThread -Dorg.eclipse.swt.internal.carbon.smallFonts -Declipse.p2.max.threads=10 -Doomph.update.url=http://download.eclipse.org/oomph/updates/milestone/latest -Doomph.redirection.index.redirection=index:/->http://git.eclipse.org/c/oomph/org.eclipse.oomph.git/plain/setups/
6335 sun.tools.jps.Jps -lmvV -Dapplication.home=/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home -Xms8m
# 3、查看java进程的线程执行状态
jstack -l 632
2018-05-24 17:20:58
Full thread dump Java HotSpot(TM) 64-Bit Server VM (25.131-b11 mixed mode):
"Attach Listener" #24 daemon prio=9 os_prio=31 tid=0x00007f85590a9000 nid=0x12913 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"logback configurator timer" #19 daemon prio=5 os_prio=31 tid=0x00007f8557a0b000 nid=0x1070b in Object.wait() [0x0000700011e05000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.util.TimerThread.mainLoop(Timer.java:552)
- locked <0x0000000786c51310> (a java.util.TaskQueue)
at java.util.TimerThread.run(Timer.java:505)
Locked ownable synchronizers:
- None
"EMF Reference Cleaner" #18 daemon prio=5 os_prio=31 tid=0x00007f8556a3c800 nid=0x11a27 in Object.wait() [0x0000700011d02000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x0000000786b047e8> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
- locked <0x0000000786b047e8> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:164)
at org.eclipse.emf.common.util.CommonUtil$1ReferenceClearingQueuePollingThread.run(CommonUtil.java:70)
Locked ownable synchronizers:
- None
"Worker-JM" #17 prio=5 os_prio=31 tid=0x00007f855a214000 nid=0x11237 in Object.wait() [0x0000700011bff000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x0000000786904e30> (a java.util.ArrayList)
at org.eclipse.core.internal.jobs.InternalWorker.run(InternalWorker.java:59)
- locked <0x0000000786904e30> (a java.util.ArrayList)
Locked ownable synchronizers:
- None
"SCR Component Actor" #16 daemon prio=5 os_prio=31 tid=0x00007f855a03f000 nid=0xcc07 in Object.wait() [0x0000700011afc000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x0000000786904fc0> (a java.util.LinkedList)
at java.lang.Object.wait(Object.java:502)
at org.apache.felix.scr.impl.ComponentActorThread.run(ComponentActorThread.java:80)
- locked <0x0000000786904fc0> (a java.util.LinkedList)
at java.lang.Thread.run(Thread.java:748)
Locked ownable synchronizers:
- None
"Framework Event Dispatcher: org.eclipse.osgi.internal.framework.EquinoxEventPublisher@41c89d2f" #15 daemon prio=5 os_prio=31 tid=0x00007f85579d7000 nid=0xca03 in Object.wait() [0x00007000119f9000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x0000000786904ff8> (a org.eclipse.osgi.framework.eventmgr.EventManager$EventThread)
at java.lang.Object.wait(Object.java:502)
at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.getNextEvent(EventManager.java:400)
- locked <0x0000000786904ff8> (a org.eclipse.osgi.framework.eventmgr.EventManager$EventThread)
at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:336)
Locked ownable synchronizers:
- None
"Start Level: Equinox Container: 5d0c2c4a-f591-4e43-8c7e-392bc4862274" #14 daemon prio=5 os_prio=31 tid=0x00007f85590c1800 nid=0xc907 in Object.wait() [0x00007000118f6000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x0000000786b04818> (a org.eclipse.osgi.framework.eventmgr.EventManager$EventThread)
at java.lang.Object.wait(Object.java:502)
at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.getNextEvent(EventManager.java:400)
- locked <0x0000000786b04818> (a org.eclipse.osgi.framework.eventmgr.EventManager$EventThread)
at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:336)
Locked ownable synchronizers:
- None
"Active Thread: Equinox Container: 5d0c2c4a-f591-4e43-8c7e-392bc4862274" #12 prio=5 os_prio=31 tid=0x00007f8557160800 nid=0xc717 waiting on condition [0x00007000117f3000]
java.lang.Thread.State: TIMED_WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x0000000780f588a8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1093)
at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:748)
Locked ownable synchronizers:
- None
"Service Thread" #10 daemon prio=9 os_prio=31 tid=0x00007f85588fe000 nid=0x9303 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"C1 CompilerThread3" #9 daemon prio=9 os_prio=31 tid=0x00007f8556812000 nid=0x9103 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"C2 CompilerThread2" #8 daemon prio=9 os_prio=31 tid=0x00007f855a001800 nid=0x8f03 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"C2 CompilerThread1" #7 daemon prio=9 os_prio=31 tid=0x00007f85588fd800 nid=0x8d03 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"C2 CompilerThread0" #6 daemon prio=9 os_prio=31 tid=0x00007f8557815000 nid=0x8b03 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"Signal Dispatcher" #5 daemon prio=9 os_prio=31 tid=0x00007f8556811000 nid=0x8903 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"Surrogate Locker Thread (Concurrent GC)" #4 daemon prio=9 os_prio=31 tid=0x00007f855a000800 nid=0x8603 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"Finalizer" #3 daemon prio=8 os_prio=31 tid=0x00007f8556810800 nid=0x8203 in Object.wait() [0x0000700010bc6000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x0000000780a00c08> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
- locked <0x0000000780a00c08> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:164)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:209)
Locked ownable synchronizers:
- None
"Reference Handler" #2 daemon prio=10 os_prio=31 tid=0x00007f85588f5000 nid=0x8003 in Object.wait() [0x0000700010ac3000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:502)
at java.lang.ref.Reference.tryHandlePending(Reference.java:191)
- locked <0x0000000780a00dc0> (a java.lang.ref.Reference$Lock)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:153)
Locked ownable synchronizers:
- None
"main" #1 prio=6 os_prio=31 tid=0x00007f855a808800 nid=0x307 runnable [0x00007fff54a1d000]
java.lang.Thread.State: RUNNABLE
at org.eclipse.swt.internal.cocoa.OS.objc_msgSend_bool(Native Method)
at org.eclipse.swt.internal.cocoa.NSRunLoop.runMode(NSRunLoop.java:42)
at org.eclipse.swt.widgets.Display.sleep(Display.java:4830)
at org.eclipse.jface.window.Window.runEventLoop(Window.java:819)
at org.eclipse.jface.window.Window.open(Window.java:794)
at org.eclipse.ui.internal.ide.ChooseWorkspaceDialog.prompt(ChooseWorkspaceDialog.java:114)
at org.eclipse.ui.internal.ide.application.IDEApplication.promptForWorkspace(IDEApplication.java:364)
at org.eclipse.ui.internal.ide.application.IDEApplication.checkInstanceLocation(IDEApplication.java:278)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:141)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:388)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:243)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:653)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:590)
at org.eclipse.equinox.launcher.Main.run(Main.java:1499)
Locked ownable synchronizers:
- None
"VM Thread" os_prio=31 tid=0x00007f85588f0800 nid=0x7e03 runnable
"Gang worker#0 (Parallel GC Threads)" os_prio=31 tid=0x00007f8558810800 nid=0x5403 runnable
"Gang worker#1 (Parallel GC Threads)" os_prio=31 tid=0x00007f8558814000 nid=0x5603 runnable
"Gang worker#2 (Parallel GC Threads)" os_prio=31 tid=0x00007f855881a800 nid=0x5803 runnable
"Gang worker#3 (Parallel GC Threads)" os_prio=31 tid=0x00007f855881b000 nid=0x5a03 runnable
"Gang worker#4 (Parallel GC Threads)" os_prio=31 tid=0x00007f855881b800 nid=0x5c03 runnable
"Gang worker#5 (Parallel GC Threads)" os_prio=31 tid=0x00007f855881c000 nid=0x5e03 runnable
"Gang worker#6 (Parallel GC Threads)" os_prio=31 tid=0x00007f855881d000 nid=0x6003 runnable
"Gang worker#7 (Parallel GC Threads)" os_prio=31 tid=0x00007f855881d800 nid=0x6203 runnable
"G1 Main Concurrent Mark GC Thread" os_prio=31 tid=0x00007f8558833800 nid=0x7603 runnable
"Gang worker#0 (G1 Parallel Marking Threads)" os_prio=31 tid=0x00007f8559003000 nid=0x7803 runnable
"Gang worker#1 (G1 Parallel Marking Threads)" os_prio=31 tid=0x00007f855a006800 nid=0x7a03 runnable
"G1 Concurrent Refinement Thread#0" os_prio=31 tid=0x00007f8558824000 nid=0x7403 runnable
"G1 Concurrent Refinement Thread#1" os_prio=31 tid=0x00007f8558823800 nid=0x7203 runnable
"G1 Concurrent Refinement Thread#2" os_prio=31 tid=0x00007f8558822800 nid=0x7003 runnable
"G1 Concurrent Refinement Thread#3" os_prio=31 tid=0x00007f8558822000 nid=0x6e03 runnable
"G1 Concurrent Refinement Thread#4" os_prio=31 tid=0x00007f8558821000 nid=0x6c03 runnable
"G1 Concurrent Refinement Thread#5" os_prio=31 tid=0x00007f8558820800 nid=0x6a03 runnable
"G1 Concurrent Refinement Thread#6" os_prio=31 tid=0x00007f855881f800 nid=0x6803 runnable
"G1 Concurrent Refinement Thread#7" os_prio=31 tid=0x00007f855881f000 nid=0x6603 runnable
"G1 Concurrent Refinement Thread#8" os_prio=31 tid=0x00007f855881e000 nid=0x6403 runnable
"String Deduplication Thread" os_prio=31 tid=0x00007f85588d7800 nid=0x7c03 runnable
"VM Periodic Task Thread" os_prio=31 tid=0x00007f855900b800 nid=0x9503 waiting on condition
JNI global references: 392
# 4、查看分类型的堆统计
jmap -heap 632
Attaching to process ID 632, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.131-b11
using thread-local object allocation.
Garbage-First (G1) GC with 8 thread(s)
Heap Configuration:
MinHeapFreeRatio = 40
MaxHeapFreeRatio = 70
MaxHeapSize = 1073741824 (1024.0MB)
NewSize = 1363144 (1.2999954223632812MB)
MaxNewSize = 643825664 (614.0MB)
OldSize = 5452592 (5.1999969482421875MB)
NewRatio = 2
SurvivorRatio = 8
MetaspaceSize = 21807104 (20.796875MB)
CompressedClassSpaceSize = 1073741824 (1024.0MB)
MaxMetaspaceSize = 17592186044415 MB
G1HeapRegionSize = 1048576 (1.0MB)
Heap Usage:
G1 Heap:
regions = 1024
capacity = 1073741824 (1024.0MB)
used = 123350528 (117.63623046875MB)
free = 950391296 (906.36376953125MB)
11.487913131713867% used
G1 Young Generation:
Eden Space:
regions = 91
capacity = 162529280 (155.0MB)
used = 95420416 (91.0MB)
free = 67108864 (64.0MB)
58.70967741935484% used
Survivor Space:
regions = 6
capacity = 6291456 (6.0MB)
used = 6291456 (6.0MB)
free = 0 (0.0MB)
100.0% used
G1 Old Generation:
regions = 21
capacity = 99614720 (95.0MB)
used = 21638656 (20.63623046875MB)
free = 77976064 (74.36376953125MB)
21.722347861842106% used
10800 interned Strings occupying 915944 bytes.
# 5、查看基于 classloader 的堆统计
jmap -clstats 632
Attaching to process ID 632, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.131-b11
finding class loader instances ..done.
computing per loader stat ..done.
please wait.. computing liveness.......liveness analysis may be inaccurate ...
class_loader classes bytes parent_loader alive? type
<bootstrap> 1413 2614211 null live <internal>
0x0000000786c19940 73 139502 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786920a10 0 0 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c793c0 69 143761 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000781400048 69 176221 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c18dc8 19 38354 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c191c8 53 109827 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c1c248 87 204940 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786b4a438 0 0 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c055d0 11 7916 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c18550 3 2593 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c1a2d0 65 118499 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786b49da0 0 0 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c063d8 184 415436 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c2c0d8 7 18717 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c79358 16 38634 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c05a60 11 12415 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c2d6e0 223 452432 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c00168 97 410884 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c05168 248 826728 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c15968 33 79295 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c15e68 60 180492 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
0x0000000786c21be8 97 212559 0x0000000780a04ed8 live org/eclipse/osgi/internal/loader/[email protected]
....
total = 73 5103 11314038 N/A alive=70, dead=3 N/A
# 6、导出堆的使用状态到一个文件
jmap -dump:live,format=b,file=heap.bin 632
jhat heap.bin
# 分析上面一步导出的堆统计文件
jhat heap.bin
Reading from heap.bin...
Dump file created Thu May 24 17:41:00 CST 2018
Snapshot read, resolving...
Resolving 269783 objects...
Chasing references, expect 53 dots.....................................................
Eliminating duplicate references.....................................................
Snapshot resolved.
Started HTTP server on port 7000
Server is ready.
# 7、在浏览器中查看堆信息
http://127.0.0.1:7000
信息的最后部分，有几个链接，可以点击，从而看到按照不同纬度进行组合、排序的统计。在查看问题的时候，应该很有用。不明白为什么不把这几个链接放在最顶部。
Other Queries
- All classes including platform
- Show all members of the rootset
- Show instance counts for all classes (including platform)
- Show instance counts for all classes (excluding platform)
- Show heap histogram
- Show finalizer summary
- Execute Object Query Language (OQL) query
例如，点击 Show instance counts for all classes (including platform)，能看到各个Class的实例个数，已经按多少降序排好，如：
-
50719 instances of class java.util.HashMap$Node
29557 instances of class java.lang.String
23679 instances of class [C
14285 instances of class java.util.HashMap
13740 instances of class [Ljava.util.HashMap$Node;
8192 instances of class [Ljava.lang.Object;
7125 instances of class java.util.HashMap$EntrySet
6766 instances of class java.util.HashMap$KeySet
6395 instances of class java.util.Collections$UnmodifiableMap
6240 instances of class java.util.Collections$UnmodifiableSet
6231 instances of class java.util.Collections$UnmodifiableMap$UnmodifiableEntrySet
6076 instances of class java.util.ArrayList
5783 instances of class org.eclipse.osgi.container.ModuleCapability
5645 instances of class org.eclipse.osgi.container.ModuleRequirement
5524 instances of class java.util.HashSet
5194 instances of class java.util.Collections$SingletonSet
5142 instances of class org.eclipse.osgi.container.ModuleWire
3458 instances of class java.lang.Class
3236 instances of class java.lang.Object
2598 instances of class java.util.Collections$SingletonMap
2597 instances of class java.util.AbstractMap$SimpleImmutableEntry
2222 instances of class java.util.Hashtable$Entry
【完】
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