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Linux下Swap空间的添加
环境：CentOS 6.2

author:? youseesan
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mkdir /var/swap

---创建指定大小的文件file.swp? 1024字节 65536/1024=64M
[root@localhost ~]# dd if=/dev/zero of=/var/swap/file.swp bs=1024 count=65536
记录了65536+0 的读入
记录了65536+0 的写出
67108864字节(67 MB)已复制，1.05399 秒，63.7 MB/秒
[root@localhost ~]#

----UUID=7b2d46b8-6448-43d5-86e0-fffa0c798965作为卷标
[root@localhost ~]# mkswap /var/swap/file.swp
mkswap: /var/swap/file.swp: warning: don't erase bootbits sectors
??????? on whole disk. Use -f to force.
Setting up swapspace version 1, size = 65532 KiB
no label, UUID=7b2d46b8-6448-43d5-86e0-fffa0c798965

vi /etc/fstab --添加下面一行,系统启动后自动加载
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/var/swap/file.swp???????? swap???????? swap??? defaults??????? 0 0
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[root@localhost ~]# free -m
???????????? total?????? used?????? free???? shared??? buffers???? cached
Mem:????????? 1266??????? 364??????? 901????????? 0???????? 17??????? 181
-/+ buffers/cache:??????? 165?????? 1100
Swap:???????? 2918????????? 0?????? 2918
[root@localhost ~]#

---开启swap添加
[root@localhost ~]# swapon /var/swap/file.swp
[root@localhost ~]# free -m
???????????? total?????? used?????? free???? shared??? buffers???? cached
Mem:????????? 1266??????? 364??????? 901????????? 0???????? 17??????? 181
-/+ buffers/cache:??????? 165?????? 1100
Swap:???????? 2982????????? 0?????? 2982
[root@localhost ~]#

---关闭swap添加
[root@localhost ~]# swapoff /var/swap/file.swp
[root@localhost ~]# free -m
???????????? total?????? used?????? free???? shared??? buffers???? cached
Mem:????????? 1266??????? 364??????? 901????????? 0???????? 17??????? 181
-/+ buffers/cache:??????? 165?????? 1100
Swap:???????? 2918????????? 0?????? 2918
[root@localhost ~]#