SWAP FILE OR SWAP SPACE

SWAPFILE OR SWAPSPACE

Add a Swap File

dd if=/dev/zero of=/swapfile bs=1024 count=65536 (6MB Swap file)

mkswap /swapfile

swapon /swapfile

/etc/fstab entry for permanent swapfile on boot time

/swapfile          swap            swap    defaults        0 0

[root@svn ~]# cat /proc/swaps

Filename    Type    Size    Used    Priority

/dev/dm-1                            partition    2031612    0    -1

/swapfile                            file    65532    0    -2

Remove the Swap File

swapoff -v /swapfile

remove it entry from /etc/fstab

rm /swapfile

[root@svn ~]# cat /proc/swaps

Filename    Type    Size    Used    Priority

/dev/dm-1                            partition    2031612    0    -1

Add a Swap Space

lvm lvcreate VolGroup00 -n LogVol02 -L 256M
OR

lvcreate VolGroup00 -n LogVol02 -L 256M

mkswap /dev/VolGroup00/LogVol02

/etc/fstab file entry for boot time swap loading

/dev/VolGroup00/LogVol02   swap     swap    defaults     0 0

enable swap space

swapon -va

check swap space

cat /proc/swaps

OR

free

Remove the Logical Volume for Swap

swapoff -v /dev/VolGroup00/LogVol02

lvm lvremove /dev/VolGroup00/LogVol02

remove the entry from /etc/fstab

cat /proc/swaps

OR

free

Extend Swap on Logical Volume

Disable Swapping for that Logical Volume

swapoff -v /dev/VolGroup00/LogVol01

Resize the Logical Volume

lvm lvresize /dev/VolGroup00/LogVol01 -L +256M

Format the new Swap Space

mkswap /dev/VolGroup00/LogVol01

Enable the Extended Logical Volume

swapon -va

Test the Swap

cat /proc/swaps

OR

free

Reduce Swap on a Logical Volume

swapoff -v /dev/VolGroup00/LogVol01

lvm lvreduce /dev/VolGroup00/LogVol01 -L -512M

mkswap /dev/VolGroup00/LogVol01

swapon -va

cat /proc/swaps

OR

free