JVM运维调优常用命令收集

Owen Jia 2019年11月14日 901次浏览

JVM调优常用命令

参考了Hinsteny-Hisoka的文章，感谢
https://www.jb51.net/article/147702.htm

基于jdk1.8

jps

查看当前机器上所有运行的java进程名称与pid(进程编号)

jps -l

[self@owen-first ~]# jps -l
1712 helloworld.jar
3702 toSay-1.1.1.jar
21994 sun.tools.jps.Jps
1100 com.aliyun.tianji.cloudmonitor.Application

jinfo

查看指定的jvm进程所有的属性设置和配置参数

jinfo pid

jmap

查看某个pid进程对应的应用程序内存占用情况

jmap -heap pid

[self@owen-first ~]# jmap -heap 3702
Attaching to process ID 3702, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 25.161-b12

using thread-local object allocation.
Mark Sweep Compact GC

Heap Configuration:
   MinHeapFreeRatio         = 40
   MaxHeapFreeRatio         = 70
   MaxHeapSize              = 268435456 (256.0MB)
   NewSize                  = 67108864 (64.0MB)
   MaxNewSize               = 134217728 (128.0MB)
   OldSize                  = 67108864 (64.0MB)
   NewRatio                 = 1
   SurvivorRatio            = 8
   MetaspaceSize            = 21807104 (20.796875MB)
   CompressedClassSpaceSize = 1073741824 (1024.0MB)
   MaxMetaspaceSize         = 17592186044415 MB
   G1HeapRegionSize         = 0 (0.0MB)

Heap Usage:
New Generation (Eden + 1 Survivor Space):
   capacity = 70582272 (67.3125MB)
   used     = 47699728 (45.49000549316406MB)
   free     = 22882544 (21.822494506835938MB)
   67.58032385242572% used
Eden Space:
   capacity = 62783488 (59.875MB)
   used     = 43811552 (41.781951904296875MB)
   free     = 18971936 (18.093048095703125MB)
   69.78196560216597% used
From Space:
   capacity = 7798784 (7.4375MB)
   used     = 3888176 (3.7080535888671875MB)
   free     = 3910608 (3.7294464111328125MB)
   49.85618270745798% used
To Space:
   capacity = 7798784 (7.4375MB)
   used     = 0 (0.0MB)
   free     = 7798784 (7.4375MB)
   0.0% used
tenured generation:
   capacity = 78106624 (74.48828125MB)
   used     = 53877384 (51.38147735595703MB)
   free     = 24229240 (23.10680389404297MB)
   68.97927632872725% used

31332 interned Strings occupying 3263472 bytes.

jhat

jvm heap analysis tool，用于分析heapdump文件，它会建立一个http/web服务器，在浏览器上面查看分析结果，默认http://localhost:7000/。

jstack

查看进程所包含所有线程的Java堆栈信息

[self@owen-first ~]# jstack 3702
2019-11-14 14:23:22
Full thread dump Java HotSpot(TM) 64-Bit Server VM (25.161-b12 mixed mode):

"Attach Listener" #1743 daemon prio=9 os_prio=0 tid=0x00007f13600ac000 nid=0x5533 waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"pool-3-thread-37" #1688 prio=5 os_prio=0 tid=0x00007f135ca08000 nid=0x51eb waiting on condition [0x00007f1354c8b000]
   java.lang.Thread.State: WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- parking to wait for  <0x00000000f4356e20> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
	at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
	at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
	at run.halo.app.event.post.AbstractVisitEventListener$PostVisitTask.run(AbstractVisitEventListener.java:101)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

......

"Reference Handler" #2 daemon prio=10 os_prio=0 tid=0x00007f138809c800 nid=0xe79 in Object.wait() [0x00007f138e3bd000]
   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 <0x00000000f802b410> (a java.lang.ref.Reference$Lock)
	at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:153)

"VM Thread" os_prio=0 tid=0x00007f1388095000 nid=0xe78 runnable 

"VM Periodic Task Thread" os_prio=0 tid=0x00007f13880e0800 nid=0xe7f waiting on condition 

JNI global references: 2336

jstat

可以实时监测系统资源占用与jvm运行情况，全称：“Java Virtual Machine statistics monitoring tool”。

// 命令语法结构：
Usage: jstat -help|-options
  jstat -<option> [-t] [-h<lines>] <vmid> [<interval> [<count>]]
 
// 参数解释：
Options — 选项，我们一般使用 -gcutil 查看gc情况
vmid — VM的进程号，即当前运行的java进程号
interval– 间隔时间，单位为秒或者毫秒
count — 打印次数，如果缺省则打印无数次
 
S0 — Heap上的 Survivor space 0 区已使用空间的百分比
S1 — Heap上的 Survivor space 1 区已使用空间的百分比
E — Heap上的 Eden space 区已使用空间的百分比
O — Heap上的 Old space 区已使用空间的百分比
P — Perm space 区已使用空间的百分比
YGC — 从应用程序启动到采样时发生 Young GC 的次数
YGCT– 从应用程序启动到采样时 Young GC 所用的时间(单位秒)
FGC — 从应用程序启动到采样时发生 Full GC 的次数
FGCT– 从应用程序启动到采样时 Full GC 所用的时间(单位秒)
GCT — 从应用程序启动到采样时用于垃圾回收的总时间(单位秒)
 
//示例
jstat -options
-class
-compiler
-gc
-gccapacity
-gccause
-gcmetacapacity
-gcnew
-gcnewcapacity
-gcold
-gcoldcapacity
-gcutil
-printcompilation
 
[self@owen-first ~]# jstat -class -t 3702
Timestamp       Loaded  Bytes  Unloaded  Bytes     Time   
       176180.9  17036 30914.4      211   302.6      21.65