6.JVM工具

C:\\Users\\zhangxue>jps -m
6392 D6_memoryAllot
8600 Jps -m
8156

C:\\Users\\zhangxue>jps -q
6392
12764
8156

C:\\Users\\zhangxue>jps -l
8324 sun.tools.jps.Jps
6392 com.zx.chapter_01_basic.D6_memoryAllot
8156

C:\\Users\\zhangxue>jps -v

8688 Jps -Denv.class.path=.;C:\\Program
Files\\Java\\jdk1.8.0_111\\lib\\dt.jar;C:\\Program
Files\\Java\\jdk1.8.0_111\\lib\\tools.jar;
-Dapplication.home=C:\\Program Files\\Java\\jdk1.8.0_111 -Xms8m

6392 D6_memoryAllot -verbose:gc -XX:+PrintGCDetails -XX:+UseSerialGC
-Xms20m -Xmx20m -Xmn10m -Dfile.encoding=UTF-8

8156 -Dosgi.requiredJavaVersion=1.8
-Dosgi.instance.area.default=@user.home/eclipse-workspace -XX:+UseG1GC
-XX:+UseStringDeduplication -Dosgi.requiredJavaVersion=1.8 -Xms256m
-Xmx1024m -javaagent:D:\\java\\eclipse-oxygen\\lombok.jar

[root@localhost bin]# jinfo -help
Usage:
    jinfo <option> <pid>
       (to connect to a running process)

where <option> is one of:
    -flag <name>         to print the value of the named VM flag
    -flag [+|-]<name>    to enable or disable the named VM flag
    -flag <name>=<value> to set the named VM flag to the given value
    -flags               to print VM flags
    -sysprops            to print Java system properties
    <no option>          to print both VM flags and system properties
    -? | -h | --help | -help to print this help message

[root@localhost bin]# jinfo -sysprops 24971 | more
Attaching to process ID 24971, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 24.79-b02
java.runtime.name = Java(TM) SE Runtime Environment
java.vm.version = 24.79-b02
sun.boot.library.path = /usr/local/java/jdk1.7.0_79/jre/lib/amd64
shared.loader =
java.vendor.url = http://java.oracle.com/
java.vm.vendor = Oracle Corporation
path.separator = :
file.encoding.pkg = sun.io
java.vm.name = Java HotSpot(TM) 64-Bit Server VM
java.util.logging.config.file =/home/yuhuo-tomcat/tomcat2/conf/logging.properties
tomcat.util.buf.StringCache.byte.enabled = true
sun.os.patch.level = unknown
sun.java.launcher = SUN_STANDARD
user.country = CN
user.dir = /home/yuhuo-tomcat/tomcat2/bin
java.vm.specification.name = Java Virtual Machine Specification
java.runtime.version = 1.7.0_79-b15
org.apache.catalina.startup.TldConfig.jarsToSkip = tomcat7-websocket.jar
java.awt.graphicsenv = sun.awt.X11GraphicsEnvironment
os.arch = amd64

[root@localhost bin]# jinfo -flag MaxPermSize 24971
-XX:MaxPermSize=85983232
jinfo -flag ThreadStackSize 24971
-XX:ThreadStackSize=1024

[root@localhost jdk1.7.0_79]# jmap --help
Usage:
    jmap -clstats <pid>
        to connect to running process and print class loader statistics
    jmap -finalizerinfo <pid>
        to connect to running process and print information on objects awaiting finalization
    jmap -histo[:live] <pid>
        to connect to running process and print histogram of java object heap
        if the "live" suboption is specified, only count live objects
    jmap -dump:<dump-options> <pid>
        to connect to running process and dump java heap
    jmap -? -h --help
        to print this help message

    dump-options:
      live         dump only live objects; if not specified,
                   all objects in the heap are dumped.
      format=b     binary format
      file=<file>  dump heap to <file>

    Example: jmap -dump:live,format=b,file=heap.bin <pid>

[root@localhost jdk1.7.0_79]# jmap -dump:live,format=b,file=dump.hprof 24971
Dumping heap to /usr/local/java/jdk1.7.0_79/dump.hprof ...
Heap dump file created

[root@localhost jdk1.7.0_79]# jmap -heap 24971
Attaching to process ID 24971, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 24.79-b02
 
using thread-local object allocation.
Parallel GC with 4 thread(s)
 
Heap Configuration:
   MinHeapFreeRatio = 0
   MaxHeapFreeRatio = 100
   MaxHeapSize      = 4146069504 (3954.0MB)
   NewSize          = 1310720 (1.25MB)
   MaxNewSize       = 17592186044415 MB
   OldSize          = 5439488 (5.1875MB)
   NewRatio         = 2
   SurvivorRatio    = 8
   PermSize         = 21757952 (20.75MB)
   MaxPermSize      = 85983232 (82.0MB)
   G1HeapRegionSize = 0 (0.0MB)
 
Heap Usage:
PS Young Generation
Eden Space:
   capacity = 517996544 (494.0MB)
   used     = 151567520 (144.54605102539062MB)
   free     = 366429024 (349.4539489746094MB)
   29.26033421566612% used
From Space:
   capacity = 41943040 (40.0MB)
   used     = 0 (0.0MB)
   free     = 41943040 (40.0MB)
   0.0% used
To Space:
   capacity = 40370176 (38.5MB)
   used     = 0 (0.0MB)
   free     = 40370176 (38.5MB)
   0.0% used
PS Old Generation
   capacity = 115343360 (110.0MB)
   used     = 32927184 (31.401809692382812MB)
   free     = 82416176 (78.59819030761719MB)
   28.54709972034801% used
PS Perm Generation
   capacity = 85983232 (82.0MB)
   used     = 54701200 (52.16712951660156MB)
   free     = 31282032 (29.832870483398438MB)
   63.6184506300019% used
 
20822 interned Strings occupying 2441752 bytes.

[root@localhost jdk1.7.0_79]# jmap -finalizerinfo 24971
Attaching to process ID 24971, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 24.79-b02
Number of objects pending for finalization: 0

[root@localhost jdk1.7.0_79]# jmap -histo:live 24971 | more
 num     #instances         #bytes  class name
----------------------------------------------
   1:        100134       14622728  <constMethodKlass>
   2:        100134       12830128  <methodKlass>
   3:         88438       12708392  [C
   4:          8271       10163584  <constantPoolKlass>
   5:         27806        9115784  [B
   6:          8271        6225312  <instanceKlassKlass>
   7:          6830        5632192  <constantPoolCacheKlass>
   8:         86717        2081208  java.lang.String
   9:          2264        1311720  <methodDataKlass>
  10:         10880         870400  java.lang.reflect.Method
  11:          8987         869888  java.lang.Class
  12:         13330         747264  [[I
  13:         11808         733872  [S
  14:         20110         643520  java.util.concurrent.ConcurrentHashMap$HashEntry
  15:         18574         594368  java.util.HashMap$Entry
  16:          3668         504592  [Ljava.util.HashMap$Entry;
  17:         30698         491168  java.lang.Integer
  18:          2247         486864  [I
  19:          7486         479104  java.net.URL
  20:          8032         453616  [Ljava.lang.Object;
  21:         10259         410360  java.util.LinkedHashMap$Entry
  22:           699         380256  <objArrayKlassKlass>
  23:          5782         277536  org.apache.catalina.loader.ResourceEntry
  24:          8327         266464  java.lang.ref.WeakReference
  25:          2374         207928  [Ljava.util.concurrent.ConcurrentHashMap$HashEntry;
  26:          3440         192640  java.util.LinkedHashMap
  27:          4779         191160  java.lang.ref.SoftReference
  28:          3576         171648  java.util.HashMap
  29:         10080         161280  java.lang.Object

[root@localhost jdk1.7.0_79]# jmap -permstat 24971
Attaching to process ID 24971, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 24.79-b02
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>   3034    18149440      null      live    <internal>
0x000000070a88fbb8  1   3048      null      dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58
0x000000070a914860  1   3064    0x0000000709035198  dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58
0x000000070a9fc320  1   3056    0x0000000709035198  dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58
0x000000070adcb4c8  1   3064    0x0000000709035198  dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58
0x000000070a913760  1   1888    0x0000000709035198  dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58
0x0000000709f3fd40  1   3032      null      dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58
0x000000070923ba78  1   3088    0x0000000709035260  dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58
0x000000070a88fff8  1   3048      null      dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58
0x000000070adcbc58  1   1888    0x0000000709035198  dead    sun/reflect/DelegatingClassLoader@0x0000000703c50b58

[root@localhost bin]# jhat -help
Usage:  jhat [-stack <bool>] [-refs <bool>] [-port <port>] [-baseline <file>] [-debug <int>] [-version] [-h|-help] <file>
 
    -J<flag>          Pass <flag> directly to the runtime system. For
              example, -J-mx512m to use a maximum heap size of 512MB
    -stack false:     Turn off tracking object allocation call stack.
    -refs false:      Turn off tracking of references to objects
    -port <port>:     Set the port for the HTTP server.  Defaults to 7000
    -exclude <file>:  Specify a file that lists data members that should
              be excluded from the reachableFrom query.
    -baseline <file>: Specify a baseline object dump.  Objects in
              both heap dumps with the same ID and same class will
              be marked as not being "new".
    -debug <int>:     Set debug level.
                0:  No debug output
                1:  Debug hprof file parsing
                2:  Debug hprof file parsing, no server
    -version          Report version number
    -h|-help          Print this help and exit
    <file>            The file to read
 
For a dump file that contains multiple heap dumps,
you may specify which dump in the file
by appending "#<number>" to the file name, i.e. "foo.hprof#3".
 
All boolean options default to "true"

[root@localhost bin]# jstack -help
Usage:
    jstack [-l] <pid>
        (to connect to running process)
    jstack -F [-m] [-l] <pid>
        (to connect to a hung process)
    jstack [-m] [-l] <executable> <core>
        (to connect to a core file)
    jstack [-m] [-l] [server_id@]<remote server IP or hostname>
        (to connect to a remote debug server)
 
Options:
    -F  to force a thread dump. Use when jstack <pid> does not respond (process is hung)
    -m  to print both java and native frames (mixed mode)
    -l  long listing. Prints additional information about locks
    -h or -help to print this help message

[root@localhost bin]# jstack 24971

"http-nio-9001-exec-1" #80 daemon prio=5 os_prio=0 tid=0x00007f769b74e800 nid=0x34b1d2 runnable [0x00007f76399d8000]
   java.lang.Thread.State: RUNNABLE
	at sun.nio.ch.ServerSocketChannelImpl.accept0(Native Method)
	at sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:249)
	- locked <0x00000000f9430058> (a java.lang.Object)
	at org.apache.tomcat.util.net.NioEndpoint.serverSocketAccept(NioEndpoint.java:79)
	at org.apache.tomcat.util.net.Acceptor.run(Acceptor.java:129)
	at java.lang.Thread.run(Thread.java:750)
	
"http-nio-9001-exec-2" #76 daemon prio=5 os_prio=0 tid=0x00007f769b645000 nid=0x34b1ce waiting on condition [0x00007f7639ddc000]
   java.lang.Thread.State: TIMED_WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- waiting for monitor entry  <0x00000000f9430058> (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:2083)
	at org.apache.tomcat.util.threads.TaskQueue.poll(TaskQueue.java:128)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1113)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:750)

"http-nio-9001-exec-3" #65 daemon prio=5 os_prio=0 tid=0x00007f769b18a800 nid=0x34b1c3 waiting on condition [0x00007f763a8e7000]
   java.lang.Thread.State: TIMED_WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- waiting to lock  <0x00000000f93dcf58> (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:2083)
	at java.util.concurrent.LinkedBlockingQueue.poll(LinkedBlockingQueue.java:467)
	at com.netflix.eureka.util.batcher.TaskExecutors$SingleTaskWorkerRunnable.run(TaskExecutors.java:245)
	at java.lang.Thread.run(Thread.java:750)	

-Dcom.sun.management.jmxremote 
-Djava.rmi.server.hostname=192.168.3.51             (jmx绑定远程主机ip)
-Dcom.sun.management.jmxremote.port=9015            (Jmx远程监听端口)
-Dcom.sun.management.jmxremote.rmi.port=9015        (Jmx的rmi谢雨远程监听端口)
-Dcom.sun.management.jmxremote.ssl=false            (禁止使用ssl)
-Dcom.sun.management.jmxremote.authenticate=false   (不启用用户认证,启动则改为true)