把tomcat服务器java最大内存使用量调整为512m，有如下两种方式：
【1】设置环境变量
[root@WWW root]# vi .bash_profile
添加 export JAVA_OPTS="-mx512m -ms128m "，重启tomcat
【2】编辑catalina.sh文件
在tomcat_home/bin/catalina.sh 这个文件里
找到下面：
# ----- Execute The Requested Command -----------------------------------------
echo "Using CATALINA_BASE: $CATALINA_BASE"
echo "Using CATALINA_HOME: $CATALINA_HOME"
echo "Using CATALINA_TMPDIR: $CATALINA_TMPDIR"
echo "Using JAVA_HOME: $JAVA_HOME"
然后增加一行．．
# ----- Execute The Requested Command -----------------------------------------
JAVA_OPTS="-server -Xmx512m -Xms128m -Djava.awt.headless=true "
echo "Using CATALINA_BASE: $CATALINA_BASE"
echo "Using CATALINA_HOME: $CATALINA_HOME"
echo "Using CATALINA_TMPDIR: $CATALINA_TMPDIR"
echo "Using JAVA_HOME: $JAVA_HOME"
最后重启tomcat
