#查询指定进程号下面的方法区使用率,jdk1.7是perm,jdk1.8是metaspace

function get_perm_use_percent()

{

    pid="$1"  //pid是目标jvm的进程号

    jdk=$(ps -ef |grep $pid | awk '{print $8}' | grep -v 'grep')

    permUsePerceng=0;

    if [[ $jdk == *java8* ]]

       then

         MetaspaceUse=$(/usr/local/java8/bin/jstat -gc $pid |awk 'NR==2{print $10}')

         MaxMetaspaceSize=$(/usr/local/java8/bin/jcmd $pid VM.flags | egrep -o "\-XX:MaxMetaspaceSize\S*")

         if [ ! $MaxMetaspaceSize ]

                then

                MaxMetaspaceSize=-1

                return $?

                 else

                MaxMetaspaceSize=${MaxMetaspaceSize#*=}

         fi

         permUsePerceng=`awk 'BEGIN{ printf "%0.4f\n" ,'${MetaspaceUse}/${MaxMetaspaceSize}*1024' }'`

       else

         PermUse=$(jstat -gc $pid |awk 'NR==2{print $10}')

         MaxPermSize=$(jcmd $pid VM.flags | egrep -o "\-XX:MaxPermSize\S*")

         if [ ! $MaxPermSize ]

           then

             MaxPermSize=-1

             return $?

           else

             MaxPermSize=${MaxPermSize#*=}

         fi

         permUsePerceng=`awk 'BEGIN{ printf "%0.4f\n" ,'$PermUse/$MaxPermSize*1024' }'`

    fi

}