Confluence diagnostics: Garbage collection exceeded time limit
Platform Notice: Data Center - This article applies to Atlassian products on the Data Center platform.
Note that this knowledge base article was created for the Data Center version of the product. Data Center knowledge base articles for non-Data Center-specific features may also work for Server versions of the product, however they have not been tested. Support for Server* products ended on February 15th 2024. If you are running a Server product, you can visit the Atlassian Server end of support announcement to review your migration options.
*Except Fisheye and Crucible
This diagnostic alert warns you when the memory allocated to garbage collection, during a set monitoring period, exceeds a set threshold (as a percentage). If garbage collection consumes too much memory, it can affect the performance of the application.
The following appears in the application log:
WARNING ; JVM ; JVM-1002 ; Garbage collection exceeded time limit ; not-detected ; ; ; {...}This alert is enabled by default in Confluence 6.11 or later.
To resolve this issue
There's no action required for this alert. However, this information may be helpful when investigating an outage or other performance issues.
What will happen if I ignore this alert?
This alert is for information only. There's no direct action required, however, because long garbage collection (GC) pauses can cause the application to crash, you may want to improve your GC configuration. See Garbage Collection (GC) Tuning Guide
Can I change the threshold?
Yes, you can change the threshold and behaviour of this alert using the following system properties:
diagnostics.jvm.garbage.collector.percent
diagnostics.jvm.garbage.collector.monitoring.period.secs
diagnostics.jvm.memory.check.period.secs
See Configuring System Properties for more information on setting system properties.