Yes I tried to stop and start Mango again but it didn't help at all.
Finally I resolved it by editing script in ma-start.bat -
"%EXECJAVA%" %JPDA% %JAVAOPTS% -server -Xmx2500m -Xms1000m -Dma.home="%MA_HOME%" -cp "%MA_CP%" com.serotonin.m2m2.Main
Maybe it's not elegant but now I see change in memory usage after starting Mango.
Thanks for help.
Greetings