I set the flag -Xmax=12g for my app. At initial launch, garbage collection happens when
young generation reaches around 3G, gc time takes around 0.5 seconds, the
interval between gc is around 5minutes. After running for a few days, gc happens much
more often than before, now every few seconds, there is a gc happening. The
good thing is that it took very short-- 0.05 seconds. I am just curious
about why JVM kicks off gc that often.