This is a cross post by Sam Van Oort, Software Engineer at CloudBees and contributor to the Jenkins project. Today I’m going to show you how easy it is to tune Jenkins Java settings to make your controllers more responsive and stable, especially with large heap sizes. The Magic Settings: Basics: -server -XX:+AlwaysPreTouch GC Logging: -Xloggc:$JENKINS_HOME/gc-%t.log -XX:NumberOfGCLogFiles=5 -XX:+UseGCLogFileRotation -XX:GCLogFileSize=20m -XX:+PrintGC -XX:+PrintGCDateStamps -XX:+PrintGCDetails -XX:+PrintHeapAtGC -XX:+PrintGCCause -XX:+PrintTenuringDistribution -XX:+PrintReferenceGC -XX:+PrintAdaptiveSizePolicy G1 GC settings: -XX:+UseG1GC -XX:+ExplicitGCInvokesConcurrent -XX:+ParallelRefProcEnabled...