Memory stacking

Whenever i play on 1.12.2 version, my memory start to rising whole time adding additional RAM usage until hits my RAM maximum of 8GBs. Which means whenever i play on 1.12.2 my RAM goes up without going down. When hits full of my memory

{ 8GB }

start to lag and i must close mc and run again to work for some time again and when hits max again i must reopen minecraft .. And also im not the only one that that happens, i tried on my friends

{ 3 }

compusters with the same result :/