Extend lvm swap volume

To extend an LVM2 swap logical volume 

(assuming /dev/VolGroup00/LogVol01 is the volume you want to extend):

1. Disable swapping for the associated logical volume:

   # swapoff -v /dev/VolGroup00/LogVol01
   

2. Resize the LVM2 logical volume by 256 MB:

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

3. Format the new swap space:

   # mkswap /dev/VolGroup00/LogVol01
   

4. Enable the extended logical volume:

   # swapon -va

https://www.centos.org/docs/5/html/5.1/Deployment_Guide/s2-swap-extending-lvm2.html