How to Enable Garbage Collection (GC) Logging in Crowd
Purpose
Garbage collection logs are useful when debugging memory-related issues within Java-based applications.
For Linux
Add the following parameters to JAVA_OPTS in your <crowd-install>/apache-tomcat/bin/setenv.sh file. Note that the <crowd-home> reference below is just a placeholder variable. Please be sure to enter the actual path for your <crowd-home> directory:
-Xloggc:<crowd-home>/logs/`date +%F_%H-%M-%S`-gc.log -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintTenuringDistribution -XX:+PrintGCCause
-XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=10 -XX:GCLogFileSize=5MFor Windows
Batch file
If you start Crowd using start_crowd.bat, add the below code to <crowd-install>/apache-tomcat/bin/setenv.bat
rem Create a timestamp with date and time, replacing ' ' with '0' and '/' with '-'
set atlassian_timestamp=%DATE:~-4%.%DATE:~4,2%.%DATE:~7,2%_%TIME:~0,2%.%TIME:~3,2%.%TIME:~6,2%
set atlassian_timestamp=%atlassian_timestamp: =0%
set atlassian_timestamp=%atlassian_timestamp:/=-%
set atlassian_logsdir=%~dp0..\logs
set JAVA_OPTS=%JAVA_OPTS% -Xloggc:"%atlassian_logsdir%\gc-%atlassian_timestamp%.log"
set JAVA_OPTS=%JAVA_OPTS% -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=10 -XX:GCLogFileSize=5M -XX:+PrintGCCause
set JAVA_OPTS=%JAVA_OPTS% -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintTenuringDistribution NB: This will create the garbage collection logs in the <crowd-install> directory.
Service
If you start Crowd as a Windows Service, add the below parameters to the service by following the "Additional Crowd Setup Options" section in this document (be sure to substitute the actual the path for your <crowd-home> directory below)
-Xloggc:<crowd-home>\logs\gc-%t.log
-XX:+PrintGCDetails
-XX:+PrintGCDateStamps
-XX:+PrintGCCause
-XX:+PrintTenuringDistribution
-XX:+UseGCLogFileRotation
-XX:NumberOfGCLogFiles=10
-XX:GCLogFileSize=5M