设置8G交换空间

#! /bin/bash

me=`whoami`
user="root"

if  free -h | awk 'NR==3' | awk '{ print $2 }' | grep -q  0B ; 
then
	echo "交换空间为空"
else 
	echo "交换空间不为空"
	exit
fi

if [ $me != $user ] ; 
then
	echo "请使用root用户来创建交换空间"
fi 

fallocate -l 8G /swapfile
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile
echo  "/swapfile   swap    swap    sw  0   0" >> /etc/fstab