如何查看GC 及jvm配置
参考 http://desert3.iteye.com/blog/1016470
[@zw_90_156 ~]$ jps
2407 Resin
10104 Resin
7378 Jps
2360 WatchdogManager
6375 start.jar
16762 Resin
10066 WatchdogManager
[@zw_90_156 ~]$ jstat -gcutil 2407 2s
S0 S1 E O P YGC YGCT FGC FGCT GCT
62.50 0.00 85.70 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.71 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.77 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.77 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.83 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.83 83.57 99.90 1538 6.043 1 0.056 6.099
查看FGC参数 如出现1,2,3,4等 则表明在频繁的FGC
JVM_ARGS: "-Xmx1024m -Xss512k -Xms1024m -XX:ParallelGCThreads=2 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:CMSInitiatingOccupancyFraction=80 -Dspring.profiles.active=product -XX:MaxPermSize=128m -XX:PermSize=128m
serial 单线程 serial old
parNew 多线程 并行 parNow old
parallel scavenge 多线程并行 parallel old （自适应调节策略） 高吞吐
cms 并发低停顿 （在并发标记和并发清除时与客户线程一起工作）
-XX:+UseConcMarkSweepGC 年老代 cms并发收集器 parNew + cms + serial Old
-XX:+UseParNewGC 新生代 parNew收集器 与cms配合使用 parNew + Serial Old
-XX:ParallelGCThreads=2 限制垃圾收集的线程数
cms 缩短垃圾收集时用户的停顿时间 serial old 年老代 cms的备份
parallel scavenge 新生代 收集器 高吞吐 吞吐量优先
-Xmx 设置最大堆
prallel scavenge 新生代 + parallel old 年老代 吞吐量优先 并行
parNew 并行 + cms 最短停顿时间 并发低停顿收集器
-XX:CMSInitiatingOccupancyFraction=80 cms收集器在年老代使用80%后被激活
-Xmx1024m -Xms1024m java堆heap大小
======================================
[@zw-90-156 ~]$ jps -l
15210 com.caucho.boot.WatchdogManager
28290 sun.tools.jps.Jps
10551 com.caucho.server.resin.Resin
7164 com.caucho.boot.WatchdogManager
14309 com.caucho.server.resin.Resin
1282 com.caucho.server.resin.Resin
28193 com.caucho.server.resin.Resin
9335 com.caucho.boot.WatchdogManager
16246 com.caucho.server.resin.Resin
8554 com.caucho.boot.WatchdogManager
13769 /opt/jetty_dev/start.jar
1242 com.caucho.boot.WatchdogManager
7204 com.caucho.server.resin.Resin
jps -mlVv localhost
jps [ options ] [ hostid ]
其中，options可以用：
-q (安静)
-m (输出传递给main方法的参数)
-l (显示完整路径)
-v (显示传递给JVM的命令行参数)
-V (显示通过flag文件传递给JVM的参数)
-J (和其他Java工具类似用于传递参数给命令本身要调用的java进程)；
hostid是主机id，默认localhost。
======================================
[@zw-90-156 ~]$ jstat -gcutil 1282 2s
S0 S1 E O P YGC YGCT FGC FGCT GCT
0.00 50.00 37.83 11.28 55.71 11 0.026 1 0.056 0.082
0.00 50.00 37.83 11.28 55.71 11 0.026 1 0.056 0.082
0.00 50.00 37.83 11.28 55.71 11 0.026 1 0.056 0.082
可以通过命令：jstat -options option，看到支持的option参数
-class (类加载器)
-compiler (JIT)
-gc (GC堆状态)
-gccapacity (各区大小)
-gccause (最近一次GC统计和原因)
-gcnew (新区统计)
-gcnewcapacity (新区大小)
-gcold (老区统计)
-gcoldcapacity (老区大小)
-gcpermcapacity (永久区大小)
-gcutil (GC统计汇总)
-printcompilation (HotSpot编译统计)
jstat -gcutil pid： 统计gc信息统计。
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
-gccapacity参数：
NGCMN：年轻代(young)中初始化(最小)的大小 (字节)
NGCMX：年轻代(young)的最大容量 (字节)
NGC：年轻代(young)中当前的容量 (字节)
S0C：年轻代中第一个survivor（幸存区）的容量 (字节)
S1C：年轻代中第二个survivor（幸存区）的容量 (字节)
EC：年轻代中Eden（伊甸园）的容量 (字节)
OGCMN：old代中初始化(最小)的大小 (字节)
OGCMX：old代的最大容量 (字节)
OGC：old代当前新生成的容量 (字节)
OC：Old代的容量 (字节)
PGCMN：perm代中初始化(最小)的大小 (字节)
PGCMX：perm代的最大容量 (字节)
PGC：perm代当前新生成的容量 (字节)
PC：Perm(持久代)的容量 (字节)
YGC：从应用程序启动到采样时年轻代中gc次数
FGC：从应用程序启动到采样时old代(全gc)gc次数
=========================================================
[@zw-90-156 ~]$ jstack -l 1282
2014-03-10 10:52:30
Full thread dump Java HotSpot(TM) 64-Bit Server VM (20.14-b01 mixed mode):
"resin-1675" daemon prio=10 tid=0x00002aaabc003000 nid=0x7009 in Object.wait() [0x0000000042834000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674c6d0> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1674" daemon prio=10 tid=0x00002aaabc006000 nid=0x6b3d in Object.wait() [0x0000000042aff000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674c520> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1673" daemon prio=10 tid=0x00002aaabc007800 nid=0x5f1f in Object.wait() [0x0000000042b81000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674c370> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1672" daemon prio=10 tid=0x00002aaabc008000 nid=0x5b0e in Object.wait() [0x0000000042875000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674c1c0> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1670" daemon prio=10 tid=0x00002aaabc002800 nid=0x38bb in Object.wait() [0x0000000041206000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674be60> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1669" daemon prio=10 tid=0x00002aaabc001800 nid=0x34a5 in Object.wait() [0x0000000042c44000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674bcb0> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1662" daemon prio=10 tid=0x00002aaac0007800 nid=0x3369 in Object.wait() [0x0000000042d07000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f6263468> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1657" daemon prio=10 tid=0x0000000041736000 nid=0x5432 in Object.wait() [0x0000000042c03000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f6262bf8> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1656" daemon prio=10 tid=0x0000000041736800 nid=0x4f7b in Object.wait() [0x00000000427f3000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f6262a48> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1653" daemon prio=10 tid=0x0000000041571800 nid=0x6837 in Object.wait() [0x0000000042c85000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f6262538> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"Attach Listener" daemon prio=10 tid=0x00002aaab04b7800 nid=0x4357 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-10$2109028635" daemon prio=10 tid=0x00002aaab04ad800 nid=0x52c waiting for monitor entry [0x0000000042b40000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-9$649272183" daemon prio=10 tid=0x00002aaab04b6000 nid=0x529 waiting for monitor entry [0x0000000042abe000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-8$458872080" daemon prio=10 tid=0x00002aaab04ba800 nid=0x528 runnable [0x00000000419ef000]
java.lang.Thread.State: RUNNABLE
at java.net.PlainSocketImpl.socketAccept(Native Method)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:408)
- locked <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-destroy" daemon prio=10 tid=0x00002aaab04b2000 nid=0x526 in Object.wait() [0x00000000411c5000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000000e10e7180> (a com.caucho.server.resin.Resin$DestroyThread)
at java.lang.Object.wait(Object.java:485)
at com.caucho.server.resin.Resin$DestroyThread.run(Resin.java:1779)
- locked <0x00000000e10e7180> (a com.caucho.server.resin.Resin$DestroyThread)
Locked ownable synchronizers:
- None
"resin-port-8087" daemon prio=10 tid=0x00002aaab04a7800 nid=0x525 in Object.wait() [0x00000000404b1000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.server.port.Port.run(Port.java:1523)
- locked <0x00000000e05de8c0> (a com.caucho.server.port.Port)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-port-6907" daemon prio=10 tid=0x00002aaaaf28e800 nid=0x524 in Object.wait() [0x000000004021f000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.server.port.Port.run(Port.java:1523)
- locked <0x00000000e05de318> (a com.caucho.server.cluster.ClusterPort)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-0$2008817593" daemon prio=10 tid=0x00002aaab039d800 nid=0x523 runnable [0x0000000042a7d000]
java.lang.Thread.State: RUNNABLE
at java.net.PlainSocketImpl.socketAccept(Native Method)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:408)
- locked <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-2$1606871064" daemon prio=10 tid=0x00002aaab036b000 nid=0x522 waiting for monitor entry [0x0000000042a3c000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-1$2075111623" daemon prio=10 tid=0x00002aaab0527800 nid=0x521 waiting for monitor entry [0x00000000429fb000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-3$1266620481" daemon prio=10 tid=0x00002aaab028a800 nid=0x520 waiting for monitor entry [0x00000000429ba000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-4$85031456" daemon prio=10 tid=0x00002aaab04e1000 nid=0x51f waiting for monitor entry [0x0000000042979000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-5$1047055737" daemon prio=10 tid=0x00002aaab048d000 nid=0x51e waiting for monitor entry [0x0000000042938000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-6$1384768241" daemon prio=10 tid=0x00002aaaaf2a5000 nid=0x51d waiting for monitor entry [0x00000000428f7000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-7$1519543948" daemon prio=10 tid=0x0000000041801000 nid=0x51c waiting for monitor entry [0x00000000428b6000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-alarm" daemon prio=10 tid=0x00002aaab04e8800 nid=0x518 waiting on condition [0x0000000041bb8000]
java.lang.Thread.State: TIMED_WAITING (sleeping)
at java.lang.Thread.sleep(Native Method)
at com.caucho.util.Alarm$AlarmThread.run(Alarm.java:586)
Locked ownable synchronizers:
- None
"resin-thread-scheduler" daemon prio=10 tid=0x00002aaab0244800 nid=0x515 in Object.wait() [0x000000004114b000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$ScheduleThread.run(ThreadPool.java:925)
- locked <0x00000000e05b6b90> (a java.util.ArrayList)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-thread-launcher" daemon prio=10 tid=0x00002aaab021f000 nid=0x514 in Object.wait() [0x00000000402cd000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$ThreadLauncher.startConnection(ThreadPool.java:858)
- locked <0x00000000e05b6c30> (a com.caucho.util.ThreadPool$ThreadLauncher)
at com.caucho.util.ThreadPool$ThreadLauncher.run(ThreadPool.java:881)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"Low Memory Detector" daemon prio=10 tid=0x00000000415f1800 nid=0x512 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"C2 CompilerThread1" daemon prio=10 tid=0x000000004160d000 nid=0x511 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"C2 CompilerThread0" daemon prio=10 tid=0x00000000415f6000 nid=0x510 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"Signal Dispatcher" daemon prio=10 tid=0x00000000415ea800 nid=0x50f runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"Finalizer" daemon prio=10 tid=0x00000000415a7000 nid=0x50e in Object.wait() [0x000000004246e000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:118)
- locked <0x00000000e05b7310> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:134)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)
Locked ownable synchronizers:
- None
"Reference Handler" daemon prio=10 tid=0x000000004159f800 nid=0x50d in Object.wait() [0x000000004242d000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:485)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:116)
- locked <0x00000000e05b7408> (a java.lang.ref.Reference$Lock)
Locked ownable synchronizers:
- None
"main" prio=10 tid=0x0000000041533000 nid=0x503 runnable [0x000000004027d000]
java.lang.Thread.State: RUNNABLE
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:129)
at java.net.SocketInputStream.read(SocketInputStream.java:182)
at com.caucho.server.resin.Resin.waitForExit(Resin.java:1270)
at com.caucho.server.resin.Resin.main(Resin.java:1372)
Locked ownable synchronizers:
- None
"VM Thread" prio=10 tid=0x0000000041599000 nid=0x50c runnable
"GC task thread#0 (ParallelGC)" prio=10 tid=0x0000000041546000 nid=0x504 runnable
"GC task thread#1 (ParallelGC)" prio=10 tid=0x0000000041548000 nid=0x505 runnable
"GC task thread#2 (ParallelGC)" prio=10 tid=0x000000004154a000 nid=0x506 runnable
"GC task thread#3 (ParallelGC)" prio=10 tid=0x000000004154b800 nid=0x507 runnable
"GC task thread#4 (ParallelGC)" prio=10 tid=0x000000004154d800 nid=0x508 runnable
"GC task thread#5 (ParallelGC)" prio=10 tid=0x000000004154f800 nid=0x509 runnable
"GC task thread#6 (ParallelGC)" prio=10 tid=0x0000000041551000 nid=0x50a runnable
"GC task thread#7 (ParallelGC)" prio=10 tid=0x0000000041553000 nid=0x50b runnable
"VM Periodic Task Thread" prio=10 tid=0x00000000415f4000 nid=0x513 waiting on condition
JNI global references: 1424
========================================================
[@zw-90-156 ~]$ jstack -F 1282
Attaching to process ID 1282, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.14-b01
Deadlock Detection:
No deadlocks found.
Thread 1152: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 28681: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 27453: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 24351: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 23310: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 14523: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 13477: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 13161: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 21554: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 20347: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 26679: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 17239: (state = BLOCKED)
Thread 1324: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1321: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1320: (state = IN_NATIVE)
- java.net.PlainSocketImpl.socketAccept(java.net.SocketImpl) @bci=0 (Interpreted frame)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=7, line=408 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1318: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- com.caucho.server.resin.Resin$DestroyThread.run() @bci=12, line=1779 (Interpreted frame)
Thread 1317: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.server.port.Port.run() @bci=85, line=1523 (Compiled frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1316: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.server.port.Port.run() @bci=85, line=1523 (Compiled frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1315: (state = IN_NATIVE)
- java.net.PlainSocketImpl.socketAccept(java.net.SocketImpl) @bci=0 (Interpreted frame)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=7, line=408 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1314: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1313: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1312: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1311: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1310: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1309: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1308: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1304: (state = BLOCKED)
- java.lang.Thread.sleep(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.Alarm$AlarmThread.run() @bci=35, line=586 (Compiled frame)
Thread 1301: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$ScheduleThread.run() @bci=90, line=925 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1300: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$ThreadLauncher.startConnection(long) @bci=214, line=858 (Compiled frame)
- com.caucho.util.ThreadPool$ThreadLauncher.run() @bci=48, line=881 (Compiled frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1295: (state = BLOCKED)
Thread 1294: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- java.lang.ref.ReferenceQueue.remove(long) @bci=44, line=118 (Interpreted frame)
- java.lang.ref.ReferenceQueue.remove() @bci=2, line=134 (Interpreted frame)
- java.lang.ref.Finalizer$FinalizerThread.run() @bci=3, line=159 (Interpreted frame)
Thread 1293: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- java.lang.ref.Reference$ReferenceHandler.run() @bci=46, line=116 (Interpreted frame)
Thread 1283: (state = IN_NATIVE)
- java.net.SocketInputStream.socketRead0(java.io.FileDescriptor, byte[], int, int, int) @bci=0 (Interpreted frame)
- java.net.SocketInputStream.read(byte[], int, int) @bci=84, line=129 (Interpreted frame)
- java.net.SocketInputStream.read() @bci=23, line=182 (Interpreted frame)
- com.caucho.server.resin.Resin.waitForExit() @bci=304, line=1270 (Interpreted frame)
- com.caucho.server.resin.Resin.main(java.lang.String[]) @bci=42, line=1372 (Interpreted frame)
=============================================================
jmap:显示java进程内存使用的相关信息
jmap pid #打印内存使用的摘要信息
jmap –heap pid #java heap信息
jmap -histo:live pid #统计对象count ，live表示在使用
jmap -histo pid >mem.txt #打印比较简单的各个有多少个对象占了多少内存的信息，一般重定向的文件
jmap -dump:format=b,file=mem.dat pid #将内存使用的详细情况输出到mem.dat 文件
jvm配置打印GC相关信息
-XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGC
对应的日志会输出到catalina的日志中去
jinfo -flag HeapDumpBeforeFullGC 29167 #查看HeapDumpBeforeFullGC
jinfo: 查看和修改JVM参数
Usage:
jinfo <option> <pid>
(to connect to a running process)
where <option> is one of:
-flag <name> to print the value of the named VM flag
-flag [+|-]<name> to enable or disable the named VM flag
-flag <name>=<value> to set the named VM flag to the given value
-h | -help to print this help message
[@zw-90-156 ~]$ jmap 1282
Attaching to process ID 1282, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.14-b01
0x0000000040000000 49K /opt/jdk1.6.0_43/bin/java
0x00000037a5600000 140K /lib64/ld-2.5.so
0x00000037a5a00000 1681K /lib64/libc-2.5.so
0x00000037a5e00000 22K /lib64/libdl-2.5.so
0x00000037a6200000 600K /lib64/libm-2.5.so
0x00000037a6600000 142K /lib64/libpthread-2.5.so
0x00000037a6e00000 52K /lib64/librt-2.5.so
0x00000037aa600000 111K /lib64/libnsl-2.5.so
0x00002aaaaaac3000 64K /opt/jdk1.6.0_43/jre/lib/amd64/libverify.so
0x00002aaaaabd2000 229K /opt/jdk1.6.0_43/jre/lib/amd64/libjava.so
0x00002aaaaad1a000 52K /lib64/libnss_files-2.5.so
0x00002aaaaaf25000 90K /opt/jdk1.6.0_43/jre/lib/amd64/libzip.so
0x00002aaaaf3d2000 38K /opt/jdk1.6.0_43/jre/lib/amd64/libmanagement.so
0x00002aaaaf4d9000 110K /opt/jdk1.6.0_43/jre/lib/amd64/libnet.so
0x00002ad21d600000 47K /opt/jdk1.6.0_43/jre/lib/amd64/jli/libjli.so
0x00002ad21d70d000 13050K /opt/jdk1.6.0_43/jre/lib/amd64/server/libjvm.so
==============================================
[@zw-90-156 ~]$ jmap -heap 1282
Attaching to process ID 1282, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.14-b01
using thread-local object allocation.
Parallel GC with 8 thread(s)
Heap Configuration:
MinHeapFreeRatio = 40
MaxHeapFreeRatio = 70
MaxHeapSize = 536870912 (512.0MB)
NewSize = 1310720 (1.25MB)
MaxNewSize = 17592186044415 MB
OldSize = 5439488 (5.1875MB)
NewRatio = 2
SurvivorRatio = 8
PermSize = 21757952 (20.75MB)
MaxPermSize = 268435456 (256.0MB)
Heap Usage:
PS Young Generation
Eden Space:
capacity = 53477376 (51.0MB)
used = 20790384 (19.827255249023438MB)
free = 32686992 (31.172744750976562MB)
38.87697107651655% used
From Space:
capacity = 65536 (0.0625MB)
used = 32768 (0.03125MB)
free = 32768 (0.03125MB)
50.0% used
To Space:
capacity = 14483456 (13.8125MB)
used = 0 (0.0MB)
free = 14483456 (13.8125MB)
0.0% used
PS Old Generation
capacity = 174915584 (166.8125MB)
used = 19734216 (18.82001495361328MB)
free = 155181368 (147.99248504638672MB)
11.28213710220354% used
PS Perm Generation
capacity = 28114944 (26.8125MB)
used = 15663608 (14.937980651855469MB)
free = 12451336 (11.874519348144531MB)
55.71274835190851% used
=======================================================
java虽然是自动回收内存，但是应用程序，尤其服务器程序最好根据业务情况指明内存分配限制。否则可能导致应用程序宕掉。
举例说明含义：
-Xms128m
表示JVM Heap(堆内存)最小尺寸128MB，初始分配
-Xmx512m
表示JVM Heap(堆内存)最大允许的尺寸256MB，按需分配。
说明：如果-Xmx不指定或者指定偏小，应用可能会导致java.lang.OutOfMemory错误，此错误来自JVM不是Throwable的，无法用try...catch捕捉。
PermSize和MaxPermSize指明虚拟机为java永久生成对象（Permanate generation）如，class对象、方法对象这些可反射（reflective）对象分配内存限制，这些内存不包括在Heap（堆内存）区之中。
-XX:PermSize=64MB 最小尺寸，初始分配
-XX:MaxPermSize=256MB 最大允许分配尺寸，按需分配
过小会导致：java.lang.OutOfMemoryError: PermGen space
MaxPermSize缺省值和-server -client选项相关。
-server选项下默认MaxPermSize为64m
-client选项下默认MaxPermSize为32m
经验：
1、慎用最小限制选项Xms,PermSize已节约系统资源。
=========================================================
近期研究对jvm的内存使用情况进行监控，因此对观察虚拟机的内存使用方法做了一些收集，对jvm的参数设置了解了一下：
几个基本概念：
PermGen space：全称是Permanent Generation space，即永久代。就是说是永久保存的区域,用于存放Class和Meta信息，Class在被Load的时候被放入该区域，GC(Garbage Collection)应该不会对PermGen space进行清理，所以如果你的APP会LOAD很多CLASS的话，就很可能出现PermGen space错误。
Heap space：存放Instance。Java Heap分为3个区，Young即新生代，Old即老生代和Permanent。Young保存刚实例化的对象。当该区被填满时，GC会将对象移到Old区。Permanent区则负责保存反射对象。
几个参数设置的意义：
xms/xmx：定义YOUNG+OLD段的总尺寸，ms为JVM启动时YOUNG+OLD的内存大小；mx为最大可占用的YOUNG+OLD内存大小。在用户生产环境上一般将这两个值设为相同，以减少运行期间系统在内存申请上所花的开销。
NewSize/MaxNewSize：定义YOUNG段的尺寸，NewSize为JVM启动时YOUNG的内存大小；MaxNewSize为最大可占用的YOUNG内存大小。在用户生产环境上一般将这两个值设为相同，以减少运行期间系统在内存申请上所花的开销。
PermSize/MaxPermSize：定义Perm段的尺寸，PermSize为JVM启动时Perm的内存大小；MaxPermSize为最大可占用的Perm内存大小。在用户生产环境上一般将这两个值设为相同，以减少运行期间系统在内存申请上所花的开销。
SurvivorRatio：设置YOUNG代中Survivor空间和Eden空间的比例
申请一块内存的过程：
A. JVM会试图为相关Java对象在Eden中初始化一块内存区域
B. 当Eden空间足够时，内存申请结束。否则到下一步
C. JVM试图释放在Eden中所有不活跃的对象（这属于1或更高级的垃圾回收）；释放后若Eden空间仍然不足以放入新对象，则试图将部分Eden中活跃对象放入Survivor区/OLD区
D. Survivor区被用来作为Eden及OLD的中间交换区域，当OLD区空间足够时，Survivor区的对象会被移到Old区，否则会被保留在Survivor区
E. 当OLD区空间不够时，JVM会在OLD区进行完全的垃圾收集（0级）
F. 完全垃圾收集后，若Survivor及OLD区仍然无法存放从Eden复制过来的部分对象，导致JVM无法在Eden区为新对象创建内存区域，则出现”out of memory错误”
我们的一种resin服务器的jvm参数设置：
“-Xmx2000M -Xms2000M -Xmn500M -XX:PermSize=250M -XX:MaxPermSize=250M -Xss256K -XX:+DisableExplicitGC -XX:SurvivorRatio=1 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+CMSParallelRemarkEnabled -XX:+UseCMSCompactAtFullCollection -XX:CMSFullGCsBeforeCompaction=0 -XX:+CMSClassUnloadingEnabled -XX:LargePageSizeInBytes=128M -XX:+UseFastAccessorMethods -XX:+UseCMSInitiatingOccupancyOnly -XX:CMSInitiatingOccupancyFraction=60 -XX:SoftRefLRUPolicyMSPerMB=0 -XX:+PrintClassHistogram -XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGC -Xloggc:log/gc.log”
是一种典型的响应时间优先型的配置。
Java中有四种不同的回收算法，对应的启动参数为
–XX:+UseSerialGC
–XX:+UseParallelGC
–XX:+UseParallelOldGC
–XX:+UseConcMarkSweepGC
1. Serial Collector
大部分平台或者强制 java -client 默认会使用这种。
young generation算法 = serial
old generation算法 = serial (mark-sweep-compact)
这种方法的缺点很明显，stop-the-world, 速度慢。服务器应用不推荐使用。
2. Parallel Collector
在linux x64上默认是这种，其他平台要加 java -server 参数才会默认选用这种。
young = parallel，多个thread同时copy
old = mark-sweep-compact = 1
优点：新生代回收更快。因为系统大部分时间做的gc都是新生代的，这样提高了throughput(cpu用于非gc时间)
缺点：当运行在8G/16G server上old generation live object太多时候pause time过长
3. Parallel Compact Collector (ParallelOld)
young = parallel = 2
old = parallel，分成多个独立的单元，如果单元中live object少则回收，多则跳过
优点：old old generation上性能较 parallel 方式有提高
缺点：大部分server系统old generation内存占用会达到60%-80%, 没有那么多理想的单元live object很少方便迅速回收，同时compact方面开销比起parallel并没明显减少。
4. Concurent Mark-Sweep(CMS) Collector
young generation = parallel collector = 2
old = cms
同时不做 compact 操作。
优点：pause time会降低, pause敏感但CPU有空闲的场景需要建议使用策略4.
缺点：cpu占用过多，cpu密集型服务器不适合。另外碎片太多，每个object的存储都要通过链表连续跳n个地方，空间浪费问题也会增大。
内存监控的方法：
1. jmap -heap pid
查看java 堆（heap）使用情况
using thread-local object allocation.
Parallel GC with 4 thread(s) //GC 方式
Heap Configuration: //堆内存初始化配置
MinHeapFreeRatio=40 //对应jvm启动参数-XX:MinHeapFreeRatio设置JVM堆最小空闲比率(default 40)
MaxHeapFreeRatio=70 //对应jvm启动参数 -XX:MaxHeapFreeRatio设置JVM堆最大空闲比率(default 70)
MaxHeapSize=512.0MB //对应jvm启动参数-XX:MaxHeapSize=设置JVM堆的最大大小
NewSize = 1.0MB //对应jvm启动参数-XX:NewSize=设置JVM堆的‘新生代’的默认大小
MaxNewSize =4095MB //对应jvm启动参数-XX:MaxNewSize=设置JVM堆的‘新生代’的最大大小
OldSize = 4.0MB //对应jvm启动参数-XX:OldSize=<value>:设置JVM堆的‘老生代’的大小
NewRatio = 8 //对应jvm启动参数-XX:NewRatio=:‘新生代’和‘老生代’的大小比率
SurvivorRatio = 8 //对应jvm启动参数-XX:SurvivorRatio=设置年轻代中Eden区与Survivor区的大小比值
PermSize= 16.0MB //对应jvm启动参数-XX:PermSize=<value>:设置JVM堆的‘永生代’的初始大小
MaxPermSize=64.0MB //对应jvm启动参数-XX:MaxPermSize=<value>:设置JVM堆的‘永生代’的最大大小
Heap Usage: //堆内存分步
PS Young Generation
Eden Space: //Eden区内存分布
capacity = 20381696 (19.4375MB) //Eden区总容量
used = 20370032 (19.426376342773438MB) //Eden区已使用
free = 11664 (0.0111236572265625MB) //Eden区剩余容量
99.94277218147106% used //Eden区使用比率
From Space: //其中一个Survivor区的内存分布
capacity = 8519680 (8.125MB)
used = 32768 (0.03125MB)
free = 8486912 (8.09375MB)
0.38461538461538464% used
To Space: //另一个Survivor区的内存分布
capacity = 9306112 (8.875MB)
used = 0 (0.0MB)
free = 9306112 (8.875MB)
0.0% used
PS Old Generation //当前的Old区内存分布
capacity = 366280704 (349.3125MB)
used = 322179848 (307.25464630126953MB)
free = 44100856 (42.05785369873047MB)
87.95982001825573% used
PS Perm Generation //当前的 “永生代” 内存分布
capacity = 32243712 (30.75MB)
used = 28918584 (27.57891082763672MB)
free = 3325128 (3.1710891723632812MB)
89.68751488662348% used
=====================================================================
jps
-q只输出进程ID，而不输出类的短名称
-m用于输出传递给Java进程（主函数）的参数
-l完整路径
-v显示传递给jvm的参数
10776@RedHat6 ~]$ jps -m -l -v
4345 sun.tools.jps.Jps -m -l -v -Denv.class.path=./:/opt/apps/jdk/lib:/opt/apps/jdk/lib/tools.jar -Dapplication.home=/opt/apps_install/jdk-1.6.0_25 -Xms8m
10776@RedHat6 ~]$ jps -q
4355
[@mhmaster.focus.cn ~]$ jps -v
14101 Resin -Dresin.server=app-0 -Djava.util.logging.manager=com.caucho.log.LogManagerImpl -Djava.system.class.loader=com.caucho.loader.SystemClassLoader -Djava.endorsed.dirs=/opt/data/jdk1.6.0_45/jre/lib/endorsed:/opt/data/resin//endorsed:/opt/data/resin//endorsed -Djavax.management.builder.initial=com.caucho.jmx.MBeanServerBuilderImpl -Djava.awt.headless=true -Dresin.home=/opt/data/resin/ -Xss1m -Xmx256m
-------------------------------------------
jstack -F 1355
Thread 1384: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.util.TimerThread.mainLoop() @bci=201, line=509 (Interpreted frame)
- java.util.TimerThread.run() @bci=1, line=462 (Interpreted frame)
Thread 1379: (state = BLOCKED)
Thread 1378: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.ref.ReferenceQueue.remove(long) @bci=44, line=118 (Interpreted frame)
- java.lang.ref.ReferenceQueue.remove() @bci=2, line=134 (Interpreted frame)
- java.lang.ref.Finalizer$FinalizerThread.run() @bci=3, line=159 (Interpreted frame)
Thread 1377: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- java.lang.ref.Reference$ReferenceHandler.run() @bci=46, line=116 (Interpreted frame)
Thread 1375: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- org.apache.hadoop.ipc.Server.join() @bci=8, line=2082 (Interpreted frame)
- org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.join() @bci=4, line=311 (Interpreted frame)
- org.apache.hadoop.hdfs.server.namenode.NameNode.join() @bci=4, line=639 (Interpreted frame)
- org.apache.hadoop.hdfs.server.namenode.NameNode.main(java.lang.String[]) @bci=39, line=1235 (Interpreted frame)
[@zw_90_156 ~]$ jps
2407 Resin
10104 Resin
7378 Jps
2360 WatchdogManager
6375 start.jar
16762 Resin
10066 WatchdogManager
[@zw_90_156 ~]$ jstat -gcutil 2407 2s
S0 S1 E O P YGC YGCT FGC FGCT GCT
62.50 0.00 85.70 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.71 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.77 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.77 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.83 83.57 99.90 1538 6.043 1 0.056 6.099
62.50 0.00 85.83 83.57 99.90 1538 6.043 1 0.056 6.099
查看FGC参数 如出现1,2,3,4等 则表明在频繁的FGC
JVM_ARGS: "-Xmx1024m -Xss512k -Xms1024m -XX:ParallelGCThreads=2 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:CMSInitiatingOccupancyFraction=80 -Dspring.profiles.active=product -XX:MaxPermSize=128m -XX:PermSize=128m
serial 单线程 serial old
parNew 多线程 并行 parNow old
parallel scavenge 多线程并行 parallel old （自适应调节策略） 高吞吐
cms 并发低停顿 （在并发标记和并发清除时与客户线程一起工作）
-XX:+UseConcMarkSweepGC 年老代 cms并发收集器 parNew + cms + serial Old
-XX:+UseParNewGC 新生代 parNew收集器 与cms配合使用 parNew + Serial Old
-XX:ParallelGCThreads=2 限制垃圾收集的线程数
cms 缩短垃圾收集时用户的停顿时间 serial old 年老代 cms的备份
parallel scavenge 新生代 收集器 高吞吐 吞吐量优先
-Xmx 设置最大堆
prallel scavenge 新生代 + parallel old 年老代 吞吐量优先 并行
parNew 并行 + cms 最短停顿时间 并发低停顿收集器
-XX:CMSInitiatingOccupancyFraction=80 cms收集器在年老代使用80%后被激活
-Xmx1024m -Xms1024m java堆heap大小
======================================
[@zw-90-156 ~]$ jps -l
15210 com.caucho.boot.WatchdogManager
28290 sun.tools.jps.Jps
10551 com.caucho.server.resin.Resin
7164 com.caucho.boot.WatchdogManager
14309 com.caucho.server.resin.Resin
1282 com.caucho.server.resin.Resin
28193 com.caucho.server.resin.Resin
9335 com.caucho.boot.WatchdogManager
16246 com.caucho.server.resin.Resin
8554 com.caucho.boot.WatchdogManager
13769 /opt/jetty_dev/start.jar
1242 com.caucho.boot.WatchdogManager
7204 com.caucho.server.resin.Resin
jps -mlVv localhost
jps [ options ] [ hostid ]
其中，options可以用：
-q (安静)
-m (输出传递给main方法的参数)
-l (显示完整路径)
-v (显示传递给JVM的命令行参数)
-V (显示通过flag文件传递给JVM的参数)
-J (和其他Java工具类似用于传递参数给命令本身要调用的java进程)；
hostid是主机id，默认localhost。
======================================
[@zw-90-156 ~]$ jstat -gcutil 1282 2s
S0 S1 E O P YGC YGCT FGC FGCT GCT
0.00 50.00 37.83 11.28 55.71 11 0.026 1 0.056 0.082
0.00 50.00 37.83 11.28 55.71 11 0.026 1 0.056 0.082
0.00 50.00 37.83 11.28 55.71 11 0.026 1 0.056 0.082
可以通过命令：jstat -options option，看到支持的option参数
-class (类加载器)
-compiler (JIT)
-gc (GC堆状态)
-gccapacity (各区大小)
-gccause (最近一次GC统计和原因)
-gcnew (新区统计)
-gcnewcapacity (新区大小)
-gcold (老区统计)
-gcoldcapacity (老区大小)
-gcpermcapacity (永久区大小)
-gcutil (GC统计汇总)
-printcompilation (HotSpot编译统计)
jstat -gcutil pid： 统计gc信息统计。
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
-gccapacity参数：
NGCMN：年轻代(young)中初始化(最小)的大小 (字节)
NGCMX：年轻代(young)的最大容量 (字节)
NGC：年轻代(young)中当前的容量 (字节)
S0C：年轻代中第一个survivor（幸存区）的容量 (字节)
S1C：年轻代中第二个survivor（幸存区）的容量 (字节)
EC：年轻代中Eden（伊甸园）的容量 (字节)
OGCMN：old代中初始化(最小)的大小 (字节)
OGCMX：old代的最大容量 (字节)
OGC：old代当前新生成的容量 (字节)
OC：Old代的容量 (字节)
PGCMN：perm代中初始化(最小)的大小 (字节)
PGCMX：perm代的最大容量 (字节)
PGC：perm代当前新生成的容量 (字节)
PC：Perm(持久代)的容量 (字节)
YGC：从应用程序启动到采样时年轻代中gc次数
FGC：从应用程序启动到采样时old代(全gc)gc次数
=========================================================
[@zw-90-156 ~]$ jstack -l 1282
2014-03-10 10:52:30
Full thread dump Java HotSpot(TM) 64-Bit Server VM (20.14-b01 mixed mode):
"resin-1675" daemon prio=10 tid=0x00002aaabc003000 nid=0x7009 in Object.wait() [0x0000000042834000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674c6d0> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1674" daemon prio=10 tid=0x00002aaabc006000 nid=0x6b3d in Object.wait() [0x0000000042aff000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674c520> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1673" daemon prio=10 tid=0x00002aaabc007800 nid=0x5f1f in Object.wait() [0x0000000042b81000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674c370> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1672" daemon prio=10 tid=0x00002aaabc008000 nid=0x5b0e in Object.wait() [0x0000000042875000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674c1c0> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1670" daemon prio=10 tid=0x00002aaabc002800 nid=0x38bb in Object.wait() [0x0000000041206000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674be60> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1669" daemon prio=10 tid=0x00002aaabc001800 nid=0x34a5 in Object.wait() [0x0000000042c44000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f674bcb0> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1662" daemon prio=10 tid=0x00002aaac0007800 nid=0x3369 in Object.wait() [0x0000000042d07000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f6263468> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1657" daemon prio=10 tid=0x0000000041736000 nid=0x5432 in Object.wait() [0x0000000042c03000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f6262bf8> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1656" daemon prio=10 tid=0x0000000041736800 nid=0x4f7b in Object.wait() [0x00000000427f3000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f6262a48> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-1653" daemon prio=10 tid=0x0000000041571800 nid=0x6837 in Object.wait() [0x0000000042c85000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:727)
- locked <0x00000000f6262538> (a com.caucho.util.ThreadPool$Item)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"Attach Listener" daemon prio=10 tid=0x00002aaab04b7800 nid=0x4357 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-10$2109028635" daemon prio=10 tid=0x00002aaab04ad800 nid=0x52c waiting for monitor entry [0x0000000042b40000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-9$649272183" daemon prio=10 tid=0x00002aaab04b6000 nid=0x529 waiting for monitor entry [0x0000000042abe000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-8$458872080" daemon prio=10 tid=0x00002aaab04ba800 nid=0x528 runnable [0x00000000419ef000]
java.lang.Thread.State: RUNNABLE
at java.net.PlainSocketImpl.socketAccept(Native Method)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:408)
- locked <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-destroy" daemon prio=10 tid=0x00002aaab04b2000 nid=0x526 in Object.wait() [0x00000000411c5000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000000e10e7180> (a com.caucho.server.resin.Resin$DestroyThread)
at java.lang.Object.wait(Object.java:485)
at com.caucho.server.resin.Resin$DestroyThread.run(Resin.java:1779)
- locked <0x00000000e10e7180> (a com.caucho.server.resin.Resin$DestroyThread)
Locked ownable synchronizers:
- None
"resin-port-8087" daemon prio=10 tid=0x00002aaab04a7800 nid=0x525 in Object.wait() [0x00000000404b1000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.server.port.Port.run(Port.java:1523)
- locked <0x00000000e05de8c0> (a com.caucho.server.port.Port)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-port-6907" daemon prio=10 tid=0x00002aaaaf28e800 nid=0x524 in Object.wait() [0x000000004021f000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.server.port.Port.run(Port.java:1523)
- locked <0x00000000e05de318> (a com.caucho.server.cluster.ClusterPort)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-0$2008817593" daemon prio=10 tid=0x00002aaab039d800 nid=0x523 runnable [0x0000000042a7d000]
java.lang.Thread.State: RUNNABLE
at java.net.PlainSocketImpl.socketAccept(Native Method)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:408)
- locked <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-2$1606871064" daemon prio=10 tid=0x00002aaab036b000 nid=0x522 waiting for monitor entry [0x0000000042a3c000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-1$2075111623" daemon prio=10 tid=0x00002aaab0527800 nid=0x521 waiting for monitor entry [0x00000000429fb000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-3$1266620481" daemon prio=10 tid=0x00002aaab028a800 nid=0x520 waiting for monitor entry [0x00000000429ba000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-4$85031456" daemon prio=10 tid=0x00002aaab04e1000 nid=0x51f waiting for monitor entry [0x0000000042979000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"http-127.0.0.1:8087-5$1047055737" daemon prio=10 tid=0x00002aaab048d000 nid=0x51e waiting for monitor entry [0x0000000042938000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e100f730> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-6$1384768241" daemon prio=10 tid=0x00002aaaaf2a5000 nid=0x51d waiting for monitor entry [0x00000000428f7000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"hmux-127.0.0.1:6907-7$1519543948" daemon prio=10 tid=0x0000000041801000 nid=0x51c waiting for monitor entry [0x00000000428b6000]
java.lang.Thread.State: BLOCKED (on object monitor)
at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:406)
- waiting to lock <0x00000000e10e7508> (a java.net.SocksSocketImpl)
at java.net.ServerSocket.implAccept(ServerSocket.java:462)
at java.net.ServerSocket.accept(ServerSocket.java:430)
at com.caucho.vfs.QServerSocketWrapper.accept(QServerSocketWrapper.java:91)
at com.caucho.server.port.Port.accept(Port.java:1179)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:659)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-alarm" daemon prio=10 tid=0x00002aaab04e8800 nid=0x518 waiting on condition [0x0000000041bb8000]
java.lang.Thread.State: TIMED_WAITING (sleeping)
at java.lang.Thread.sleep(Native Method)
at com.caucho.util.Alarm$AlarmThread.run(Alarm.java:586)
Locked ownable synchronizers:
- None
"resin-thread-scheduler" daemon prio=10 tid=0x00002aaab0244800 nid=0x515 in Object.wait() [0x000000004114b000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$ScheduleThread.run(ThreadPool.java:925)
- locked <0x00000000e05b6b90> (a java.util.ArrayList)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"resin-thread-launcher" daemon prio=10 tid=0x00002aaab021f000 nid=0x514 in Object.wait() [0x00000000402cd000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at com.caucho.util.ThreadPool$ThreadLauncher.startConnection(ThreadPool.java:858)
- locked <0x00000000e05b6c30> (a com.caucho.util.ThreadPool$ThreadLauncher)
at com.caucho.util.ThreadPool$ThreadLauncher.run(ThreadPool.java:881)
at java.lang.Thread.run(Thread.java:662)
Locked ownable synchronizers:
- None
"Low Memory Detector" daemon prio=10 tid=0x00000000415f1800 nid=0x512 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"C2 CompilerThread1" daemon prio=10 tid=0x000000004160d000 nid=0x511 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"C2 CompilerThread0" daemon prio=10 tid=0x00000000415f6000 nid=0x510 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"Signal Dispatcher" daemon prio=10 tid=0x00000000415ea800 nid=0x50f runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
"Finalizer" daemon prio=10 tid=0x00000000415a7000 nid=0x50e in Object.wait() [0x000000004246e000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:118)
- locked <0x00000000e05b7310> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:134)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)
Locked ownable synchronizers:
- None
"Reference Handler" daemon prio=10 tid=0x000000004159f800 nid=0x50d in Object.wait() [0x000000004242d000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:485)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:116)
- locked <0x00000000e05b7408> (a java.lang.ref.Reference$Lock)
Locked ownable synchronizers:
- None
"main" prio=10 tid=0x0000000041533000 nid=0x503 runnable [0x000000004027d000]
java.lang.Thread.State: RUNNABLE
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:129)
at java.net.SocketInputStream.read(SocketInputStream.java:182)
at com.caucho.server.resin.Resin.waitForExit(Resin.java:1270)
at com.caucho.server.resin.Resin.main(Resin.java:1372)
Locked ownable synchronizers:
- None
"VM Thread" prio=10 tid=0x0000000041599000 nid=0x50c runnable
"GC task thread#0 (ParallelGC)" prio=10 tid=0x0000000041546000 nid=0x504 runnable
"GC task thread#1 (ParallelGC)" prio=10 tid=0x0000000041548000 nid=0x505 runnable
"GC task thread#2 (ParallelGC)" prio=10 tid=0x000000004154a000 nid=0x506 runnable
"GC task thread#3 (ParallelGC)" prio=10 tid=0x000000004154b800 nid=0x507 runnable
"GC task thread#4 (ParallelGC)" prio=10 tid=0x000000004154d800 nid=0x508 runnable
"GC task thread#5 (ParallelGC)" prio=10 tid=0x000000004154f800 nid=0x509 runnable
"GC task thread#6 (ParallelGC)" prio=10 tid=0x0000000041551000 nid=0x50a runnable
"GC task thread#7 (ParallelGC)" prio=10 tid=0x0000000041553000 nid=0x50b runnable
"VM Periodic Task Thread" prio=10 tid=0x00000000415f4000 nid=0x513 waiting on condition
JNI global references: 1424
========================================================
[@zw-90-156 ~]$ jstack -F 1282
Attaching to process ID 1282, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.14-b01
Deadlock Detection:
No deadlocks found.
Thread 1152: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 28681: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 27453: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 24351: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 23310: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 14523: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 13477: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 13161: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 21554: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 20347: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 26679: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=224, line=727 (Compiled frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 17239: (state = BLOCKED)
Thread 1324: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1321: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1320: (state = IN_NATIVE)
- java.net.PlainSocketImpl.socketAccept(java.net.SocketImpl) @bci=0 (Interpreted frame)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=7, line=408 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1318: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- com.caucho.server.resin.Resin$DestroyThread.run() @bci=12, line=1779 (Interpreted frame)
Thread 1317: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.server.port.Port.run() @bci=85, line=1523 (Compiled frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1316: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.server.port.Port.run() @bci=85, line=1523 (Compiled frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1315: (state = IN_NATIVE)
- java.net.PlainSocketImpl.socketAccept(java.net.SocketImpl) @bci=0 (Interpreted frame)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=7, line=408 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1314: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1313: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1312: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1311: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1310: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1309: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1308: (state = BLOCKED)
- java.net.PlainSocketImpl.accept(java.net.SocketImpl) @bci=0, line=406 (Interpreted frame)
- java.net.ServerSocket.implAccept(java.net.Socket) @bci=60, line=462 (Interpreted frame)
- java.net.ServerSocket.accept() @bci=48, line=430 (Interpreted frame)
- com.caucho.vfs.QServerSocketWrapper.accept(com.caucho.vfs.QSocket) @bci=9, line=91 (Interpreted frame)
- com.caucho.server.port.Port.accept(com.caucho.server.port.TcpConnection, boolean) @bci=142, line=1179 (Interpreted frame)
- com.caucho.server.port.TcpConnection.run() @bci=328, line=659 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.runTasks() @bci=278, line=743 (Interpreted frame)
- com.caucho.util.ThreadPool$Item.run() @bci=106, line=662 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1304: (state = BLOCKED)
- java.lang.Thread.sleep(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.Alarm$AlarmThread.run() @bci=35, line=586 (Compiled frame)
Thread 1301: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$ScheduleThread.run() @bci=90, line=925 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1300: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- com.caucho.util.ThreadPool$ThreadLauncher.startConnection(long) @bci=214, line=858 (Compiled frame)
- com.caucho.util.ThreadPool$ThreadLauncher.run() @bci=48, line=881 (Compiled frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 1295: (state = BLOCKED)
Thread 1294: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- java.lang.ref.ReferenceQueue.remove(long) @bci=44, line=118 (Interpreted frame)
- java.lang.ref.ReferenceQueue.remove() @bci=2, line=134 (Interpreted frame)
- java.lang.ref.Finalizer$FinalizerThread.run() @bci=3, line=159 (Interpreted frame)
Thread 1293: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- java.lang.ref.Reference$ReferenceHandler.run() @bci=46, line=116 (Interpreted frame)
Thread 1283: (state = IN_NATIVE)
- java.net.SocketInputStream.socketRead0(java.io.FileDescriptor, byte[], int, int, int) @bci=0 (Interpreted frame)
- java.net.SocketInputStream.read(byte[], int, int) @bci=84, line=129 (Interpreted frame)
- java.net.SocketInputStream.read() @bci=23, line=182 (Interpreted frame)
- com.caucho.server.resin.Resin.waitForExit() @bci=304, line=1270 (Interpreted frame)
- com.caucho.server.resin.Resin.main(java.lang.String[]) @bci=42, line=1372 (Interpreted frame)
=============================================================
jmap:显示java进程内存使用的相关信息
jmap pid #打印内存使用的摘要信息
jmap –heap pid #java heap信息
jmap -histo:live pid #统计对象count ，live表示在使用
jmap -histo pid >mem.txt #打印比较简单的各个有多少个对象占了多少内存的信息，一般重定向的文件
jmap -dump:format=b,file=mem.dat pid #将内存使用的详细情况输出到mem.dat 文件
jvm配置打印GC相关信息
-XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGC
对应的日志会输出到catalina的日志中去
jinfo -flag HeapDumpBeforeFullGC 29167 #查看HeapDumpBeforeFullGC
jinfo: 查看和修改JVM参数
Usage:
jinfo <option> <pid>
(to connect to a running process)
where <option> is one of:
-flag <name> to print the value of the named VM flag
-flag [+|-]<name> to enable or disable the named VM flag
-flag <name>=<value> to set the named VM flag to the given value
-h | -help to print this help message
[@zw-90-156 ~]$ jmap 1282
Attaching to process ID 1282, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.14-b01
0x0000000040000000 49K /opt/jdk1.6.0_43/bin/java
0x00000037a5600000 140K /lib64/ld-2.5.so
0x00000037a5a00000 1681K /lib64/libc-2.5.so
0x00000037a5e00000 22K /lib64/libdl-2.5.so
0x00000037a6200000 600K /lib64/libm-2.5.so
0x00000037a6600000 142K /lib64/libpthread-2.5.so
0x00000037a6e00000 52K /lib64/librt-2.5.so
0x00000037aa600000 111K /lib64/libnsl-2.5.so
0x00002aaaaaac3000 64K /opt/jdk1.6.0_43/jre/lib/amd64/libverify.so
0x00002aaaaabd2000 229K /opt/jdk1.6.0_43/jre/lib/amd64/libjava.so
0x00002aaaaad1a000 52K /lib64/libnss_files-2.5.so
0x00002aaaaaf25000 90K /opt/jdk1.6.0_43/jre/lib/amd64/libzip.so
0x00002aaaaf3d2000 38K /opt/jdk1.6.0_43/jre/lib/amd64/libmanagement.so
0x00002aaaaf4d9000 110K /opt/jdk1.6.0_43/jre/lib/amd64/libnet.so
0x00002ad21d600000 47K /opt/jdk1.6.0_43/jre/lib/amd64/jli/libjli.so
0x00002ad21d70d000 13050K /opt/jdk1.6.0_43/jre/lib/amd64/server/libjvm.so
==============================================
[@zw-90-156 ~]$ jmap -heap 1282
Attaching to process ID 1282, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.14-b01
using thread-local object allocation.
Parallel GC with 8 thread(s)
Heap Configuration:
MinHeapFreeRatio = 40
MaxHeapFreeRatio = 70
MaxHeapSize = 536870912 (512.0MB)
NewSize = 1310720 (1.25MB)
MaxNewSize = 17592186044415 MB
OldSize = 5439488 (5.1875MB)
NewRatio = 2
SurvivorRatio = 8
PermSize = 21757952 (20.75MB)
MaxPermSize = 268435456 (256.0MB)
Heap Usage:
PS Young Generation
Eden Space:
capacity = 53477376 (51.0MB)
used = 20790384 (19.827255249023438MB)
free = 32686992 (31.172744750976562MB)
38.87697107651655% used
From Space:
capacity = 65536 (0.0625MB)
used = 32768 (0.03125MB)
free = 32768 (0.03125MB)
50.0% used
To Space:
capacity = 14483456 (13.8125MB)
used = 0 (0.0MB)
free = 14483456 (13.8125MB)
0.0% used
PS Old Generation
capacity = 174915584 (166.8125MB)
used = 19734216 (18.82001495361328MB)
free = 155181368 (147.99248504638672MB)
11.28213710220354% used
PS Perm Generation
capacity = 28114944 (26.8125MB)
used = 15663608 (14.937980651855469MB)
free = 12451336 (11.874519348144531MB)
55.71274835190851% used
=======================================================
java虽然是自动回收内存，但是应用程序，尤其服务器程序最好根据业务情况指明内存分配限制。否则可能导致应用程序宕掉。
举例说明含义：
-Xms128m
表示JVM Heap(堆内存)最小尺寸128MB，初始分配
-Xmx512m
表示JVM Heap(堆内存)最大允许的尺寸256MB，按需分配。
说明：如果-Xmx不指定或者指定偏小，应用可能会导致java.lang.OutOfMemory错误，此错误来自JVM不是Throwable的，无法用try...catch捕捉。
PermSize和MaxPermSize指明虚拟机为java永久生成对象（Permanate generation）如，class对象、方法对象这些可反射（reflective）对象分配内存限制，这些内存不包括在Heap（堆内存）区之中。
-XX:PermSize=64MB 最小尺寸，初始分配
-XX:MaxPermSize=256MB 最大允许分配尺寸，按需分配
过小会导致：java.lang.OutOfMemoryError: PermGen space
MaxPermSize缺省值和-server -client选项相关。
-server选项下默认MaxPermSize为64m
-client选项下默认MaxPermSize为32m
经验：
1、慎用最小限制选项Xms,PermSize已节约系统资源。
=========================================================
近期研究对jvm的内存使用情况进行监控，因此对观察虚拟机的内存使用方法做了一些收集，对jvm的参数设置了解了一下：
几个基本概念：
PermGen space：全称是Permanent Generation space，即永久代。就是说是永久保存的区域,用于存放Class和Meta信息，Class在被Load的时候被放入该区域，GC(Garbage Collection)应该不会对PermGen space进行清理，所以如果你的APP会LOAD很多CLASS的话，就很可能出现PermGen space错误。
Heap space：存放Instance。Java Heap分为3个区，Young即新生代，Old即老生代和Permanent。Young保存刚实例化的对象。当该区被填满时，GC会将对象移到Old区。Permanent区则负责保存反射对象。
几个参数设置的意义：
xms/xmx：定义YOUNG+OLD段的总尺寸，ms为JVM启动时YOUNG+OLD的内存大小；mx为最大可占用的YOUNG+OLD内存大小。在用户生产环境上一般将这两个值设为相同，以减少运行期间系统在内存申请上所花的开销。
NewSize/MaxNewSize：定义YOUNG段的尺寸，NewSize为JVM启动时YOUNG的内存大小；MaxNewSize为最大可占用的YOUNG内存大小。在用户生产环境上一般将这两个值设为相同，以减少运行期间系统在内存申请上所花的开销。
PermSize/MaxPermSize：定义Perm段的尺寸，PermSize为JVM启动时Perm的内存大小；MaxPermSize为最大可占用的Perm内存大小。在用户生产环境上一般将这两个值设为相同，以减少运行期间系统在内存申请上所花的开销。
SurvivorRatio：设置YOUNG代中Survivor空间和Eden空间的比例
申请一块内存的过程：
A. JVM会试图为相关Java对象在Eden中初始化一块内存区域
B. 当Eden空间足够时，内存申请结束。否则到下一步
C. JVM试图释放在Eden中所有不活跃的对象（这属于1或更高级的垃圾回收）；释放后若Eden空间仍然不足以放入新对象，则试图将部分Eden中活跃对象放入Survivor区/OLD区
D. Survivor区被用来作为Eden及OLD的中间交换区域，当OLD区空间足够时，Survivor区的对象会被移到Old区，否则会被保留在Survivor区
E. 当OLD区空间不够时，JVM会在OLD区进行完全的垃圾收集（0级）
F. 完全垃圾收集后，若Survivor及OLD区仍然无法存放从Eden复制过来的部分对象，导致JVM无法在Eden区为新对象创建内存区域，则出现”out of memory错误”
我们的一种resin服务器的jvm参数设置：
“-Xmx2000M -Xms2000M -Xmn500M -XX:PermSize=250M -XX:MaxPermSize=250M -Xss256K -XX:+DisableExplicitGC -XX:SurvivorRatio=1 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+CMSParallelRemarkEnabled -XX:+UseCMSCompactAtFullCollection -XX:CMSFullGCsBeforeCompaction=0 -XX:+CMSClassUnloadingEnabled -XX:LargePageSizeInBytes=128M -XX:+UseFastAccessorMethods -XX:+UseCMSInitiatingOccupancyOnly -XX:CMSInitiatingOccupancyFraction=60 -XX:SoftRefLRUPolicyMSPerMB=0 -XX:+PrintClassHistogram -XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGC -Xloggc:log/gc.log”
是一种典型的响应时间优先型的配置。
Java中有四种不同的回收算法，对应的启动参数为
–XX:+UseSerialGC
–XX:+UseParallelGC
–XX:+UseParallelOldGC
–XX:+UseConcMarkSweepGC
1. Serial Collector
大部分平台或者强制 java -client 默认会使用这种。
young generation算法 = serial
old generation算法 = serial (mark-sweep-compact)
这种方法的缺点很明显，stop-the-world, 速度慢。服务器应用不推荐使用。
2. Parallel Collector
在linux x64上默认是这种，其他平台要加 java -server 参数才会默认选用这种。
young = parallel，多个thread同时copy
old = mark-sweep-compact = 1
优点：新生代回收更快。因为系统大部分时间做的gc都是新生代的，这样提高了throughput(cpu用于非gc时间)
缺点：当运行在8G/16G server上old generation live object太多时候pause time过长
3. Parallel Compact Collector (ParallelOld)
young = parallel = 2
old = parallel，分成多个独立的单元，如果单元中live object少则回收，多则跳过
优点：old old generation上性能较 parallel 方式有提高
缺点：大部分server系统old generation内存占用会达到60%-80%, 没有那么多理想的单元live object很少方便迅速回收，同时compact方面开销比起parallel并没明显减少。
4. Concurent Mark-Sweep(CMS) Collector
young generation = parallel collector = 2
old = cms
同时不做 compact 操作。
优点：pause time会降低, pause敏感但CPU有空闲的场景需要建议使用策略4.
缺点：cpu占用过多，cpu密集型服务器不适合。另外碎片太多，每个object的存储都要通过链表连续跳n个地方，空间浪费问题也会增大。
内存监控的方法：
1. jmap -heap pid
查看java 堆（heap）使用情况
using thread-local object allocation.
Parallel GC with 4 thread(s) //GC 方式
Heap Configuration: //堆内存初始化配置
MinHeapFreeRatio=40 //对应jvm启动参数-XX:MinHeapFreeRatio设置JVM堆最小空闲比率(default 40)
MaxHeapFreeRatio=70 //对应jvm启动参数 -XX:MaxHeapFreeRatio设置JVM堆最大空闲比率(default 70)
MaxHeapSize=512.0MB //对应jvm启动参数-XX:MaxHeapSize=设置JVM堆的最大大小
NewSize = 1.0MB //对应jvm启动参数-XX:NewSize=设置JVM堆的‘新生代’的默认大小
MaxNewSize =4095MB //对应jvm启动参数-XX:MaxNewSize=设置JVM堆的‘新生代’的最大大小
OldSize = 4.0MB //对应jvm启动参数-XX:OldSize=<value>:设置JVM堆的‘老生代’的大小
NewRatio = 8 //对应jvm启动参数-XX:NewRatio=:‘新生代’和‘老生代’的大小比率
SurvivorRatio = 8 //对应jvm启动参数-XX:SurvivorRatio=设置年轻代中Eden区与Survivor区的大小比值
PermSize= 16.0MB //对应jvm启动参数-XX:PermSize=<value>:设置JVM堆的‘永生代’的初始大小
MaxPermSize=64.0MB //对应jvm启动参数-XX:MaxPermSize=<value>:设置JVM堆的‘永生代’的最大大小
Heap Usage: //堆内存分步
PS Young Generation
Eden Space: //Eden区内存分布
capacity = 20381696 (19.4375MB) //Eden区总容量
used = 20370032 (19.426376342773438MB) //Eden区已使用
free = 11664 (0.0111236572265625MB) //Eden区剩余容量
99.94277218147106% used //Eden区使用比率
From Space: //其中一个Survivor区的内存分布
capacity = 8519680 (8.125MB)
used = 32768 (0.03125MB)
free = 8486912 (8.09375MB)
0.38461538461538464% used
To Space: //另一个Survivor区的内存分布
capacity = 9306112 (8.875MB)
used = 0 (0.0MB)
free = 9306112 (8.875MB)
0.0% used
PS Old Generation //当前的Old区内存分布
capacity = 366280704 (349.3125MB)
used = 322179848 (307.25464630126953MB)
free = 44100856 (42.05785369873047MB)
87.95982001825573% used
PS Perm Generation //当前的 “永生代” 内存分布
capacity = 32243712 (30.75MB)
used = 28918584 (27.57891082763672MB)
free = 3325128 (3.1710891723632812MB)
89.68751488662348% used
=====================================================================
jps
-q只输出进程ID，而不输出类的短名称
-m用于输出传递给Java进程（主函数）的参数
-l完整路径
-v显示传递给jvm的参数
10776@RedHat6 ~]$ jps -m -l -v
4345 sun.tools.jps.Jps -m -l -v -Denv.class.path=./:/opt/apps/jdk/lib:/opt/apps/jdk/lib/tools.jar -Dapplication.home=/opt/apps_install/jdk-1.6.0_25 -Xms8m
10776@RedHat6 ~]$ jps -q
4355
[@mhmaster.focus.cn ~]$ jps -v
14101 Resin -Dresin.server=app-0 -Djava.util.logging.manager=com.caucho.log.LogManagerImpl -Djava.system.class.loader=com.caucho.loader.SystemClassLoader -Djava.endorsed.dirs=/opt/data/jdk1.6.0_45/jre/lib/endorsed:/opt/data/resin//endorsed:/opt/data/resin//endorsed -Djavax.management.builder.initial=com.caucho.jmx.MBeanServerBuilderImpl -Djava.awt.headless=true -Dresin.home=/opt/data/resin/ -Xss1m -Xmx256m
-------------------------------------------
jstack -F 1355
Thread 1384: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.util.TimerThread.mainLoop() @bci=201, line=509 (Interpreted frame)
- java.util.TimerThread.run() @bci=1, line=462 (Interpreted frame)
Thread 1379: (state = BLOCKED)
Thread 1378: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.ref.ReferenceQueue.remove(long) @bci=44, line=118 (Interpreted frame)
- java.lang.ref.ReferenceQueue.remove() @bci=2, line=134 (Interpreted frame)
- java.lang.ref.Finalizer$FinalizerThread.run() @bci=3, line=159 (Interpreted frame)
Thread 1377: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- java.lang.ref.Reference$ReferenceHandler.run() @bci=46, line=116 (Interpreted frame)
Thread 1375: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- org.apache.hadoop.ipc.Server.join() @bci=8, line=2082 (Interpreted frame)
- org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.join() @bci=4, line=311 (Interpreted frame)
- org.apache.hadoop.hdfs.server.namenode.NameNode.join() @bci=4, line=639 (Interpreted frame)
- org.apache.hadoop.hdfs.server.namenode.NameNode.main(java.lang.String[]) @bci=39, line=1235 (Interpreted frame)