make a swap file on the fly

Disclaimer: this should only be used if you can’t partition your drive by yourself, or it would be a hazzle to do so. I’ve used that method to make one compile process work, otherwise I don’t really need it.

1. Check for present swap space

   if there’s any output you might consider another solutions

   sudo swapon -s

2. Create the actual file

   bs = times count equals filesize, in this case 1gb

   sudo dd if=/dev/zero of=/swapfile bs=1024 count=1024k

3. Alternative:

4. Create a linux swap area

   sudo mkswap /swapfile

   Output looks something like this:

   Setting up swapspace version 1, size = 262140 KiB no label, UUID=103c4545-5fc5-47f3-a8b3-dfbdb64fd7eb

   sudo swapon -s

5. Activate the swap file

   sudo swapon /swapfile

   Now `swapon -s` should show something like this

   Filename Type Size Used Priority /swapfile file 262140 0 -1

6. Make it persistent in the /etc/fstab with the following entry

   /swapfile none swap sw 0 0

7. Make swappiness 0, otherwise performance will be poor. So it’s just an emergency buffer

   echo 0 > /proc/sys/vm/swappiness

8. make swappiness persistent

   echo 'vm.swappiness=0' > /etc/sysctl.conf

9. A bit of good practice, since this is root’s business

   chown root:root /swapfile chmod 0600 /swapfile