Crashes and Performance Troubleshooting
Troubleshooting Confluence performance problems requires distinguishing between different kinds of problems. The definitions below will help to clarify the problem for your own research and for the quick resolution of an Atlassian support issue.
Confluence "crashed", "hangs" or "went down"
The terms crash, hang, and went down do not describe the problem with Confluence specifically enough to help with diagnosing or resolving the problem.
See the list of more specific descriptions below to see which matches the problem most closely.
Confluence fails to start
A very serious problem is a startup issue, where Confluence prints an error message to the logs when it starts and will not respond to any requests at all. If Confluence does not resume processing requests normally after being restarted, follow Confluence Startup Problems Troubleshooting.
Articles on Confluence failing to start:
Confluence is not responding
If Confluence is not responding during a period of normal operation, there is usually a serious performance problem on the server which is preventing requests being processed normally. If the server is not responding, the Confluence administrator should follow the Troubleshooting Confluence hanging or crashing guide. Additionally, verify if the issue is related to a JVM memory problem, as insufficient heap size can cause unresponsiveness. Refer to the 'JVM Issues' section for details on addressing heap memory errors.
Articles that address Confluence not responding:
Confluence is responding slowly
A performance issue is when Confluence responds slowly to requests. You should take note of whether some kinds of pages load faster than others. If all the pages in the application are slow to respond, review the Troubleshooting Confluence hanging or crashing guide.
If Confluence is responding slowly on just a few pages, you can look at Performance Tuning to look for specific performance tuning ideas. This is the point when you should begin to gather all the information in Requesting Performance Support. Troubleshooting Slow Performance Using Page Request Profiling is especially useful when particular pages are loading slowly.
Articles that address Confluence responding slowly:
Confluence is displaying errors in the UI
If Confluence returns error pages, take note of:
- which operations in the application return error pages
- which users are affected.
If the error pages are displayed only after a long wait, you should look at the Confluence is responding slowly section above. If the error pages return quickly, follow the Troubleshooting Problems and Requesting Technical Support guide.
JVM Issues
If Confluence does not respond to requests at all, the java process for Confluence is no longer running, and there is an hs_err_pid*.log file, the JVM has crashed. One common cause is an 'OutOfMemoryError: Java heap space'. This error occurs when the allocated Java heap memory is insufficient for Confluence's requirements. Symptoms may include unresponsiveness, instability, or crashes during operation. To resolve this issue, increase the Java heap memory allocation by adjusting the Xms (initial memory) and Xmx (maximum memory) parameters. For most environments, a minimum of 4 GB heap size is recommended, and this value can be adjusted based on server resources and instance size. Refer to the 'Configuring System Properties' or 'How to Increase Heap Memory for Confluence' articles for step-by-step instructions.
Articles that address JVM issues:
Performance Data Collector
See How to use the Performance Data Collector for more information.