[jboss-user] Threads in runnable state

[Anand Raman]

hi all

Our production environment consists of Apache in front of the jboss
installation and communicating over AJP protocol on port 8009. We are
seeing many threads in the following state

"TP-Processor1537" daemon prio=1 tid=0x2faeada0 nid=0x5623 runnable
[0x1f56f000..0x1f56fe20]
        at java.net.SocketInputStream.socketRead0(Native Method)
        at java.net.SocketInputStream.read(SocketInputStream.java:129)
        at java.io.BufferedInputStream.fill(BufferedInputStream.java:218)
        at java.io.BufferedInputStream.read1(BufferedInputStream.java:256)
        at java.io.BufferedInputStream.read(BufferedInputStream.java:313)
        - locked <0x80de4330> (a java.io.BufferedInputStream)
        at org.apache.jk.common.ChannelSocket.read(ChannelSocket.java:620)
        at org.apache.jk.common.ChannelSocket.receive(ChannelSocket.java:558)
        at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:685)
        at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:889)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
        at java.lang.Thread.run(Thread.java:595)

We take a thread dump at 5 minutes interval and find that threads
continue to be in this state. While I understand the frequency of
thread dump is very low, we have seen some threads move to doing some
actual work and finally returning to this state.

I would like to understand what these threads are doing. Why don’t
these threads return to the normal wait state

"TP-Processor1535" daemon prio=1 tid=0x30fca128 nid=0x5621 in
Object.wait() [0x1f8f6000..0x1f8f7120]
        at java.lang.Object.wait(Native Method)
        - waiting on <0x66735340> (a
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable)
        at java.lang.Object.wait(Object.java:474)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:656)
        - locked <0x66735340> (a
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable)
        at java.lang.Thread.run(Thread.java:595)

Any help would be greatly appreciated.

Thanks in advance

anand