Linux下添加刪除swap空間

#需求因系統內存資源緊張急需添加10G swap 交換空間

#創建存放swap文件的目錄

[root@localhost ~]# mkdir /swap

[root@localhost ~]# dd if=/dev/zero of=/swap/swap bs=1024M count=10
10+0 records in
10+0 records out
10737418240 bytes (11 GB) copied, 20.745 s, 518 MB/s

[root@localhost ~]# mkswap /swap/swap
mkswap: /swap/swap: warning: don't erase bootbits sectors
        on whole disk. Use -f to force.
Setting up swapspace version 1, size = 10485756 KiB
no label, UUID=844fb94b-c5e5-4d55-a091-c310b9e5e289

[root@VM_37_0_centos ryzc]# free -m
             total       used       free     shared    buffers     cached
Mem:         24028      22842       1185          0        149       3530
-/+ buffers/cache:      19162       4866
Swap:         2047       1127        920

[root@localhost ~]# swapon /swap/swap

[root@localhost ~]# free -m
             total       used       free     shared    buffers     cached
Mem:         24028      22888       1139          0        150       3563
-/+ buffers/cache:      19174       4853
Swap:        12287       1125      11162

[root@localhost ~]# tail -1 /etc/rc.local 
swapon /swap/swap

[root@localhost ~]# swapoff /swap/swap 
[root@localhost ~]# rm -rf /swap/swap