Swap空间扩展

查看现有的内存和swap

[root@localhost home]# free -m
              total        used        free      shared  buff/cache   available
Mem:           1819         614         116          27        1088         965
Swap:          2047           0        2047

安装Oracle11g需要swap大概为内存2倍，需要扩展2G左右

进行swap空间新增

1.使用dd创建swapfile，bs单位默认为byte可手动指定为M或G，count为计数

[root@localhost home]# dd if=/dev/zero of=swapfile bs=1M count=2048
2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 1.96745 s, 1.1 GB/s
[root@localhost home]# ll -h
-rw-r--r--   1 root root 2.0G Aug 10 15:58 swapfile

2.使用mkswap创建交换文件

[root@localhost home]# mkswap swapfile
Setting up swapspace version 1, size = 2097148 KiB
no label, UUID=aad23206-f04b-4122-b862-e489001ed6b4

3.使用swapon激活

[root@localhost home]# swapon swapfile
swapon: /home/swapfile: insecure permissions 0644, 0600 suggested.
#建议修改权限为0600
[root@localhost home]# swapoff swapfile
[root@localhost home]# chmod 0600 swapfile 
[root@localhost home]# swapon swapfile

4.在/etc/fstab下进行添加，使swap永久生效

[root@localhost home]# vim /etc/fstab
/home/swapfile          swap                    swap    defaults        0 0

5.添加完成，查看swap分区，和总空间。

[root@localhost home]# swapon
NAME           TYPE      SIZE USED PRIO
/dev/dm-1      partition   2G   0B   -2
/home/swapfile file        2G   0B   -3
[root@localhost home]# free -m | grep Swap
Swap:          4095           0        4095

来自为知笔记(Wiz)