linux swap交換分區

創建空間

$ swapon -s

$ dd if=/dev/zero of=/mnt/swap bs=1024 count=10240

10240+0 records in
10240+0 records out
10485760 bytes (10 MB) copied, 0.0270904 s, 387 MB/s

$ mkswap /mnt/swap

Setting up swapspace version 1, size = 10236 KiB
no label, UUID=3ffe08b8-1681-47ae-992c-76108d73a5a2

$ free -h

              total        used        free      shared  buff/cache   available
Mem:           7.6G        3.4G        741M        828K        3.6G        4.0G
Swap:            0B          0B          0B

$ swapon /mnt/swap

swapon: /mnt/swap: insecure permissions 0644, 0600 suggested.

$ chmod 600 /mnt/swap

設置重啓之後還會生效
$ vi /etc/fstab
#添加如下行
/mnt/swap swap swap defaults 0 0

#重啓系統
$ reboot

擴展空間

$ dd if=/dev/zero of=/mnt/swap bs=1024 count=1024000

1024000+0 records in
1024000+0 records out
1048576000 bytes (1.0 GB) copied, 9.38812 s, 112 MB/s

$ swapon /mnt/swap

#擴展之後,直接執行報錯,需要再添加爲swap文件=>mkswap
swapon: /mnt/swap: read swap header failed: Invalid argument

$ mkswap /mnt/swap

Setting up swapspace version 1, size = 1023996 KiB
no label, UUID=18139b2d-ce48-41f4-877e-26ce1fe25f35

$ swapon /mnt/swap

$ swapon -s

Filename				Type		Size	Used	Priority
/mnt/swap                              	file	1023996	0	-2

$ free -h

              total        used        free      shared  buff/cache   available
Mem:           7.6G        3.3G        2.5G        620K        1.8G        4.1G
Swap:          999M          0B        999M

關閉交換

$ swapoff /mnt/swap

$ free -h

              total        used        free      shared  buff/cache   available
Mem:           7.6G        3.2G        3.6G        620K        855M        4.2G
Swap:            0B          0B          0B