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Mustgather: Setup for hang or performance problems on Windows

Technote (troubleshooting)


If your Java application experiences perceived hang or performance problems on a Windows operating system, there are a number of diagnostic data files that are useful for diagnosing the problem. This mustgather document describes about the required settings to be in place in order to generate those diagnostic data files.

Resolving the problem

In order to collect the diagnostic data files required for diagnosing the hang or performance problems, check that the following specific settings are configured before running your application:
1. Enable javacore generation
2. Enable core dump generation
Please enable full dump settings for Windows.
3. Enable verbose GC collection
Please use -verbose:gc option for the same.
4. Enable process sizes monitoring
5. Enable paging usage monitoring
6. Enable processor usage monitoring
7. Install the tprof utilities and enable the tprof log collection using the below option:

Please note that both the javacore and core dump generation can be enabled
using the below single Xdump option:

In case, if the above Xdump option does not generate the core dump as expected, please refer and use the Microsoft ADPlus tool to generate the core dump at the time of hang as appropriate.

Another easier way to quickly identify the performance bottlenecks and improve the efficiency of your Java application is to use the IBM® Monitoring and Diagnostic Tools for Java – Health Center tool. It also helps you to assess the status of the running Java application.

Using the IBM Monitoring and Diagnostic Tools for Java - Health Center

Information about installing and configuring the Health Center tool is provided at:

The IBM Health Center is a low overhead monitoring tool which runs alongside an IBM Java application and provides a comprehensive view of the "health" of various subsystems. Please refer the IBM Health Center document for more information.

For more details about enabling these settings, please see the related information links.

Related information

Verbose GC
Core dump
TProf usage on Windows
MS ADPlus tool to generate core dump
Health Center

Document information

More support for: Runtimes for Java Technology
Hangs/Performance Degradation

Software version: 5.0, 6.0, 6.1, 7.0, 7.1, 8.0

Operating system(s): Windows

Software edition: J2SE

Reference #: 1222470

Modified date: 07 March 2017