Main JVM memory parameters:
-Xms: Set the initial heap size when the Java application starts
-Xmx: Set the maximum heap size that a Java application can get
-Xss: Set thread stack size
-XX:MinHeapFreeRatio: Set the minimum free ratio of heap space. When the free memory of the heap space is less than this value, the JVM will expand the heap space
-XX:MaxHeapFreeRatio: Set the maximum free ratio of heap space. When the free memory of the heap space is greater than this value, the JVM will compress the heap space
-XX:NewSize: Set the new generation size
-XX:NewRatio: Set the ratio of the old generation to the new generation
-XX:SurviorRatio: Set the ratio of the eden area to the survivor area in the new generation
-XX:PermSize: Set the initial permanent generation size
-XX:MaxPermSize: Set the maximum permanent generation size
-XX:TargetSurvivorRatio: Set the available ratio of survivor area. When the space usage of the survivor area reaches this value, the object will be sent to the old age
