linux : removing swap space

reducing swap on an LVM2 logical volume
to reduce an LVM2 swap logical volume (ex. /dev/swap is the volume you want to extend):

1. disable swapping for the associated logical volume:

   swapoff -v /dev/swap

2. reduce the LVM2 logical volume by 512 MB:

   lvm lvreduce /dev/swap -L -512M

3. format the new swap space:

   mkswap /dev/swap

4. enable the extended logical volume:

   swapon -va

5. test that the logical volume has been reduced properly:

   cat /proc/swaps
   free

removing an LVM2 logical volume for swap
to remove a swap volume group (assuming /dev/swap is the swap volume you want to remove):

1. disable swapping for the associated logical volume:

   swapoff -v /dev/swap

2. remove the LVM2 logical volume of size 512 MB:

   lvm lvremove /dev/swap

3. remove the following entry from the /etc/fstab file:

   /dev/swap   swap     swap    defaults     0 0

4. test that the logical volume has been extended properly:

   cat /proc/swaps
   free

removing a swap file

1. at a shell prompt as root, execute the following command to disable the swap file (where /swapfile is the swap file):

   swapoff -v /swapfile

2. remove its entry from the /etc/fstab file.

3. Remove the actual file:

   rm /swapfile