linux上swap的查看与调整

1.查看SWAP[root@192 oc]# cat /proc/swaps
Filename Type Size Used Priority
/dev/sda3 partition 8024 104 -1
[root@192 oc]# 2.通过DD创建文件[root@192 oc]# dd if=/dev/zero of=/oc/swap bs=512 count=2000000
2000000+0 records in
2000000+0 records out
1024000000 bytes (1.0 GB) copied, 23.4213 seconds, 43.7 MB/s
[root@192 oc]#
[root@192 oc]# ll
总计 1001012
drwx------ 2 root root 16384 06-03 06:56 lost+found
-rw-r--r-- 1 root root 1024000000 06-12 10:24 swap
drwxr-xr-x 4 root root 4096 06-08 16:15 tmp
[root@192 oc]#
3.转化为swap格式
[root@192 oc]# mkswap /oc/swap
Setting up swapspace version 1, size = 1023995 kB
[root@192 oc]#

[root@192 oc]# free
total used free shared buffers cached
Mem: 1035108 1018168 16940 0 14716 892500
-/+ buffers/cache: 110952 924156
Swap: 8024 104 7920
[root@192 oc]#
启用，加入到swap池中。[root@192 oc]# swapon /oc/swap
[root@192 oc]# free
total used free shared buffers cached
Mem: 1035108 1018228 16880 0 14748 892592
-/+ buffers/cache: 110888 924220
Swap: 1008016 104 1007912
[root@192 oc]# [root@192 oc]# cat /proc/swaps
Filename Type Size Used Priority
/dev/sda3 partition 8024 104 -1
/oc/swap file 999992 0 -4
[root@192 oc]# 从swap池中拿掉[root@192 oc]# swapoff /oc/swap
[root@192 oc]# free
total used free shared buffers cached
Mem: 1035108 1018780 16328 0 15096 892760
-/+ buffers/cache: 110924 924184
Swap: 8024 104 7920
[root@192 oc]# cat /proc/swaps
Filename Type Size Used Priority
/dev/sda3 partition 8024 104 -1
[root@192 oc]#
开机自动启动：[root@192 oc]# echo "/oc/swap swap swap defaults 0 0" >> /etc/fstab
[root@192 oc]# cat /etc/fstab
LABEL=/ / ext3 defaults 1 1
LABEL=/boot /boot ext3 defaults 1 2
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
LABEL=SWAP-sda3 swap swap defaults 0 0
/dev/sdb1 /oa ext3 defaults 0 0
/dev/sdc1 /ob ext3 defaults 0 0
/dev/sdd1 /oc ext3 defaults 0 0
/dev/hdc /media/dvd iso9660 ro,auto 0 0
/oc/swap swap swap defaults 0 0
[root@192 oc]#
另：将整个设备划为swap分区fdisk时代码为82 linux swap，分区后：# mkswap /dev/sdc3
# swapon /dev/sdc3