Atlassian Jira Diagnostics plugin may cause an OutOfMemory error

Summary

In situations where the number of "expensive" JQLs identified by the Atlassian Diagnostics plugin is high enough, Jira might end up running out of memory due to the number of objects stored in the heap.

Steps to Reproduce

TBD

Expected Results

Non-optimized JQLs will be stored in the database.

Actual Results

JQLs that generated an alert in the plugin will pile in the heap causing constant full GC cycles and OOM errors.

Workaround

We can increase the threshold of the alerts based on the query time with the following JVM argument:

jira.diagnostics.thresholds.slow-query-millis=4000

• Note that the default value for this parameter is 400.

Alternatively, we can disable the Atlassian Diagnostics plugin through the Manage Apps page - this plugin will be found in the System Add-ons section.