Identifying Web container threads in a javacore or thread dump

Technote (FAQ)
Problem
How to identify Web container threads within a javacore or thread dump of an application server.
Solution
An idle thread is a thread that is ready to receive work but does not have a connection established with the plug-in or client.

A keep alive thread is an idle thread that is ready to receive work and does have a connection established with the plug-in or client.

For V3.5 releases (does not have ability to do keep-alive)

Idle thread
"Worker#20" (TID:0x8f2748, sys_thread_t:0x23aa1e98, state:R, native ID:0xc58) prio=5
at com.ibm.servlet.engine.oselistener.outofproc.NativeServerQueueImp.nativeGetSeviceMessageId
at com.ibm.servlet.engine.oselistener.outofproc.NativeServerQueueImp.getSeviceMessageId
at com.ibm.servlet.engine.oselistener.serverqueue.SQWrapperEventSource$SelectRunnable.getNewConnectionFromQueue
at com.ibm.servlet.engine.oselistener.serverqueue.SQWrapperEventSource$SelectRunnable.run
at com.ibm.servlet.engine.oselistener.outofproc.OutOfProcThread$CtlRunnable.run
at java.lang.Thread.run

For V4.0 releases

Idle thread
"Servlet.Engine.Transports:20" (TID:0x2DDA748, sys_thread_t:0xB032598, state:R, native ID:0x1000) prio=5
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:429)
at com.ibm.ws.util.CachedThread.waitForRunner(ThreadPool.java:74)
at com.ibm.ws.util.CachedThread.run(ThreadPool.java:134)

Keep-alive thread
"Servlet.Engine.Transports:20" daemon prio=5 tid=0x905d40 nid=0x37 runnable [0xed481000..0xed4819d8]
at java.net.SocketInputStream.socketRead(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:86)
at com.ibm.ws.io.Stream.read(Stream.java)
at com.ibm.ws.io.ReadStream.readBuffer(ReadStream.java)
at com.ibm.ws.io.ReadStream.read(ReadStream.java)
at com.ibm.ws.http.HttpRequest.readRequestLine(HttpRequest.java)
at com.ibm.ws.http.HttpRequest.readRequest(HttpRequest.java)
at com.ibm.ws.http.HttpConnection.readAndHandleRequest(HttpConnection.java)
at com.ibm.ws.http.HttpConnection.run(HttpConnection.java)
at com.ibm.ws.util.CachedThread.run(ThreadPool.java)

For V5.0 and V5.1 releases

Idle thread
"Servlet.Engine.Transports : 20" (TID:0x427F190, sys_thread_t:0x15D175E8, state:R, native ID:0xBB8) prio=5
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:429)
at com.ibm.ws.util.BoundedBuffer.take(BoundedBuffer.java:161)
at com.ibm.ws.util.ThreadPool.getTask(ThreadPool.java(Compiled Code))
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java(Compiled Code))

Keep-alive thread (non-SSL)
"Servlet.Engine.Transports : 20" (TID:0x427F190, sys_thread_t:0x15D175E8, state:R, native ID:0xBB8) prio=5
at java.net.SocketInputStream.socketRead(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:86)
at com.ibm.ws.io.Stream.read(Stream.java)
at com.ibm.ws.io.ReadStream.readBuffer(ReadStream.java)
at com.ibm.ws.io.ReadStream.read(ReadStream.java)
at com.ibm.ws.http.HttpRequest.readRequestLine(HttpRequest.java)
at com.ibm.ws.http.HttpRequest.readRequest(HttpRequest.java)
at com.ibm.ws.http.HttpConnection.readAndHandleRequest(HttpConnection.java)
at com.ibm.ws.http.HttpConnection.run(HttpConnection.java)
at com.ibm.ws.util.CachedThread.run(ThreadPool.java)

Keep-alive thread (SSL)
"Servlet.Engine.Transports : 12" (TID:0x458DBA18, sys_thread_t:0x60B297C0, state:R, native ID:0x427E) prio=5
at java.net.SocketInputStream.socketRead(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java(Compiled Code))
at com.ibm.sslite.s.a(Unknown Source)(Compiled Code)
at com.ibm.sslite.s.b(Unknown Source)(Compiled Code)
at com.ibm.sslite.s.a(Unknown Source)(Compiled Code)
at com.ibm.sslite.a.read(Unknown Source)(Compiled Code)
at com.ibm.jsse.a.read(Unknown Source)(Compiled Code)
at com.ibm.ws.io.Stream.read(Stream.java(Compiled Code))
at com.ibm.ws.io.ReadStream.readBuffer(ReadStream.java(Inlined Compiled Code))
at com.ibm.ws.io.ReadStream.read(ReadStream.java(Inlined Compiled Code))
at com.ibm.ws.http.HttpRequest.readRequestLine(HttpRequest.java(Compiled Code))
at com.ibm.ws.http.HttpRequest.readRequest(HttpRequest.java(Compiled Code))
at com.ibm.ws.http.HttpConnection.readAndHandleRequest(HttpConnection)
at com.ibm.ws.http.HttpConnection.run(HttpConnection.java(Compiled Code))
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:672)

Thread that is in the process of reading the request line and request headers (non-SSL)
at java.net.SocketInputStream.socketRead(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:85)
at com.ibm.ws.io.Stream.read(Stream.java:17)
at com.ibm.ws.io.ReadStream.readBuffer(ReadStream.java:411)
at com.ibm.ws.io.ReadStream.read(ReadStream.java:110)
at com.ibm.ws.http.HttpConnection.run(HttpConnection.java:448)
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:672)

Thread that is in the process of reading the request line and request headers (SSL)
"Servlet.Engine.Transports : 108" (TID:0x30591D08, sys_thread_t:0x60B02020, state:R, native ID:0x47DB) prio=5
at java.net.SocketInputStream.socketRead(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java(Compiled Code))
at com.ibm.sslite.s.a(Unknown Source)(Compiled Code)
at com.ibm.sslite.s.b(Unknown Source)(Compiled Code)
at com.ibm.sslite.s.a(Unknown Source)(Compiled Code)
at com.ibm.sslite.a.read(Unknown Source)(Compiled Code)
at com.ibm.jsse.a.read(Unknown Source)(Compiled Code)
at com.ibm.ws.io.Stream.read(Stream.java(Compiled Code))
at com.ibm.ws.io.ReadStream.readBuffer(ReadStream.java(Compiled Code))
at com.ibm.ws.io.ReadStream.read(ReadStream.java(Inlined Compiled Code))
at com.ibm.ws.http.HttpConnection.run(HttpConnection.java(Compiled Code))
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:672)











Document Information

Product categories: Software, Application Servers, Distributed Application & Web Servers, WebSphere Application Server, Servlet Engine/Web Container
Operating system(s): AIX, HPUX, Linux, Multi-Platform, Solaris, Windows
Software version: 3.5, 4.0, 5.0
Software edition: Edition Independent
Reference #: 1137491
IBM Group: Software Group
Modified date: 2004-08-01