Yor*_*m G 5 java performance centos jstack
我试图调查为什么我的jboss占用600%的CPU(在CentOS 5上运行).
我运行top -H并尝试将结果与jstack输出进行比较.大多数来自顶部的线程ID出现在jstack的输出中,但不幸的是,占用大部分CPU的线程没有列在那里.
因为输出很长,我只在这里列出它的一部分.
$top -b -n1 -H -p <jboss pid>
top - 08:04:58 up 73 days, 19:50, 1 user, load average: 5.72, 5.97, 5.95
Tasks: 128 total, 6 running, 122 sleeping, 0 stopped, 0 zombie
Cpu(s): 63.6%us, 1.7%sy, 0.0%ni, 34.2%id, 0.3%wa, 0.0%hi, 0.2%si, 0.0%st
Mem: 32946160k total, 32545228k used, 400932k free, 86776k buffers
Swap: 34996216k total, 136k used, 34996080k free, 21577176k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
12908 jboss 16 0 9488m 8.6g 18m S 71.5 27.4 146:45.68 java
12903 jboss 16 0 9488m 8.6g 18m S 69.5 27.4 146:36.08 java
12904 jboss 16 0 9488m 8.6g 18m S 69.5 27.4 146:39.63 java
12905 jboss 16 0 9488m 8.6g 18m S 69.5 27.4 146:44.46 java
12906 jboss 16 0 9488m 8.6g 18m S 69.5 27.4 146:53.94 java
12907 jboss 16 0 9488m 8.6g 18m S 69.5 27.4 146:39.18 java
12914 jboss 16 0 9488m 8.6g 18m R 27.8 27.4 36:26.64 java
12901 jboss 25 0 9488m 8.6g 18m S 0.0 27.4 0:00.00 java
12902 jboss 25 0 9488m 8.6g 18m S 0.0 27.4 0:00.05 java
12909 jboss 23 0 9488m 8.6g 18m S 0.0 27.4 76:34.09 java
12910 jboss 23 0 9488m 8.6g 18m S 0.0 27.4 76:33.49 java
12911 jboss 15 0 9488m 8.6g 18m S 0.0 27.4 257:10.35 java
12915 jboss 15 0 9488m 8.6g 18m S 0.0 27.4 0:06.63 java
12916 jboss 15 0 9488m 8.6g 18m S 0.0 27.4 0:19.61 java
more lines....
jstack outpout如下
# /usr/java/jdk1.6.0_33/bin/jstack -F 3362
Deadlock Detection:
No deadlocks found.
Thread 13055: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=415 (Interpreted frame)
- org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=441 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 12996: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=415 (Interpreted frame)
- org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=441 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
Thread 12994: (state = BLOCKED)
- java.lang.Object.wait(long) @bci=0 (Interpreted frame)
- java.lang.Object.wait() @bci=2, line=485 (Interpreted frame)
- org.apache.tomcat.util.net.JIoEndpoint$Worker.await() @bci=8, line=415 (Interpreted frame)
- org.apache.tomcat.util.net.JIoEndpoint$Worker.run() @bci=11, line=441 (Interpreted frame)
- java.lang.Thread.run() @bci=11, line=662 (Interpreted frame)
更多堆栈....
输出中的线程ID jstack也出现在输出中,top但是来自顶部的CPU密集度最高的线程ID (1903-1908)没有出现在jstack的输出中.
我以为这些可以是GC线程,但我找不到任何证明这一点的东西.
知道为什么我没有看到jstack中的所有线程或者我能做些什么来查看丢失的线程？
尝试在 jboss 所有者下运行 jstack。这样您将获得更多线程作为输出。通过发行
jstack -l 12345
我有
"Service Thread" #9 daemon prio=9 os_prio=0 tid=0x00007f976c0d3000 nid=0x1f56a runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
Locked ownable synchronizers:
- None
请注意，nid 是从 top -H 获取的线程 id 的十六进制表示形式