The problem is: when devs have learned about a necessary tuning knob, it's almost impossible to get them to stop touching it. So recent JDKs have a sane defaul

The problem is: when devs have learned about a necessary tuning knob, it's almost impossible to get them to stop touching it. So recent JDKs have a sane default. Finally. Now we have a zillion app from the time defaults were not sane, each having a few -Xm parameters in their config. If they work well enough, nobody takes the effort to remove them. If they don't work, just type a higher number and test. Manual JVM memory tuning will stay with us forever.