Removing a Swap File From Use

If you have unneeded swap space, you can remove it.

How to Remove a Swap Volume in a ZFS Root Environment

Most systems require some amount of swap space configured. If your system's swap space requirements change, then you might need to remove a swap volume before you can increase or decrease space allocated for swap. On a busy system, it might be easier to create a second swap volume if you need to increase swap space rather than trying to remove a swap volume that is busy just to increase its size.

1. Become an administrator.
2. If the swap volume is in use, then you might not be able to delete it. Check to see if the swap area is in use.

   # swap -l
   swapfile             dev    swaplo   blocks     free
   /dev/zvol/dsk/rpool/swap 102,2        16 16646128 16646128

   In the above output, blocks == free, so the swap device is not actually being used.

3. If the swap area is not is use, remove the swap area.

   # swap -d /dev/zvol/dsk/rpool/swap

4. Edit the /etc/vfstab file and delete the entry for the swap volume.
5. Verify that the swap volume is no longer available.

   # swap -l