The Java Concurrent Mark & Sweep (CMS) garbage collection algorithm aims to minimize pause times by marking and sweeping memory concurrently. Despite its benefits, CMS has been deprecated since JDK 9 and removed in JDK 14. This post discusses tuning techniques, JVM parameters, and advanced options to optimize CMS performance for specific scenarios.
When studying Garbage Collection performance, focus on 'GC Pause Duration' instead of 'GC Duration' as it more accurately reflects application performance impact. 'GC Pause Duration' includes only full pause events, while 'GC Duration' accounts for overall time, leading to potentially misleading analyses. Tools like GCeasy help differentiate these metrics effectively.