If this problem occurs when tomcat is started alone, it should be in the /bin/catalina.bat file under the directory
Add the following line above "echo "Using CATALINA_BASE: $CATALINA_BASE""
Add set JAVA_OPTS=%JAVA_OPTS% -server -XX:PermSize=128M -XX:MaxPermSize=512m According to the actual situation of your own machine.
If this problem occurs when starting in myeclipse, if the startup parameter path of tomcat is set in myeclipse: Myeclipse->preferences->myeclipse->servers->tomcat->tomcat×.×->,
-Xms1024M -Xmx1024M -XX:MaxPermSize=400M