The IBM® WebSphere® Application Server Utilities Hung Thread Interrupter (HTI) allows a user to interrupt a hung thread automatically or manually. The HTI is written in Java™ and can be used with the WebSphere Application Server V6.1 or V7.0. The HTI runs with the WebSphere Application Server for Microsoft Windows, Linux, IBM AIX, and IBM z/OS.
Java does not provide a general mechanism to forcibly interrupt threads. The HTI improves availability of WebSphere Application Server by supporting the termination of individual hung threads without restarting the entire Java virtual machine.
To use the HTI, install the HTI into WebSphere Application Server and specify the name of the target application. The HTI applies bytecode instrumentation to the specified application, so that you can interrupt a hung thread if the hung thread is executing within the specified application.
The HTI targets hanging scenarios such as an external server wait, an infinite loop, or a deadlock. To cover these scenarios, the HTI makes the following three primitive operations in Java interruptible:
- A socket wait
- A loop
- A monitor enter
The HTI can be also used by the Thread Hang Recovery (THR) utility of WebSphere Application Server for z/OS V7.0. THR tries to interrupt a hung thread if a request via IIOP, HTTP, MDB, or some other source has timed out. When the HTI is installed, THR can also use the HTI to interrupt a hung thread.
For additional information, see the User's Guide.
The HTI can be used with the WebSphere Application Server V6.1 or V7.0. It requires ASM 3.1 or higher for its bytecode instrumentation. The ASM can be downloaded from the ASM website of the OW2 Consortium.
After you downloaded the HTI archive and the ASM, you can install it as follows:
- Create an installation directory and make that directory the current working directory.
- Extract the HTI archive into the installation directory.
- Save the ASM file into the sub-directory jars using the name asm-all.jar.
- Start the target server.
- Run the installation script:
$WAS_HOME/bin/wsadmin.sh -lang jython -f jython/install.jy nodeName serverName
- Restart the target server.
- WebSphere Application Server (See also the developerWorks WebSphere Application Server zone.)
- WebSphere Application Server for z/OS
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|Hung Thread Interrupter download||hti.zip||158 KB||HTTP|