一、不重启电脑，禁用启用swap，立刻生效

禁用命令

sudo swapoff -a

启用命令

sudo swapon -a

查看交换分区的状态

sudo free -m

二、重新启动电脑，永久禁用Swap

把根目录文件系统设为可读写

sudo mount -n -o remount,rw /

用vi修改/etc/fstab文件，在swap分区这行最后前加 # 禁用掉，保存退出

vi /etc/fstab

# /etc/fstab: static file system information.
# 
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/ubuntu-vg/ubuntu-lv during curtin installation
/dev/disk/by-id/dm-uuid-LVMoJdB5hd1wqgmN8pkMEpzoO9bzCpQSGh1CHUL4mBKz7GDWrrPLPvcYFm55N0GaTj0 / ext4 defaults 0 1
# /boot was on /dev/sda2 during curtin installation
# /dev/disk/by-uuid/efcb9c31-4c38-4a72-8d53-21632274890f /boot ext4 defaults 0 1 /swap.img       none    swap    sw      0       0

重新启动电脑，使

用free -m查看分区状态

reboot
sudo free -m