分配swap文件

fallocate -l 4G /swapfile
ls -lh /swapfile
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile
swapon --show
cp /etc/fstab /etc/fstab.bak
echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab

配置swap

cat /proc/sys/vm/swappiness
echo 'vm.swappiness=10' | sudo tee -a /etc/sysctl.conf
sysctl vm.swappiness=10
echo 'vm.vfs_cache_pressure=50' | sudo tee -a /etc/sysctl.conf
sysctl vm.vfs_cache_pressure=50

删除swap

swapoff /swapfile
rm -rf /swapfile