清理内存

flushcase.sh：

echo "vm.drop_caches = 1" > /etc/sysctl.conf
#sysctl -p

while [ 1 ]
do

free_size=$(free | grep "Mem"  | awk '{print $4}')

if [ "$free_size" -le "32768" ]
then
 sync
 #date
 #echo stb current free size=$free_size
 echo 1 > /proc/sys/vm/drop_caches
fi

sleep 1

done

#To free pagecache:
#echo 1 > /proc/sys/vm/drop_caches
#To free dentries and inodes:
#echo 2 > /proc/sys/vm/drop_caches
#To free pagecache, dentries and inodes:
#echo 3 > /proc/sys/vm/drop_caches