Move swap contents back to the RAM once there's free memory

Question

So I understand that swap mem is used when computer runs out of space on ram.

Once there is available space in the memory how can I move contents of swap to ram so taht it doesn't slow me down?

Answer 1

If you really have enough RAM to not need swap, then issue:

/sbin/swapoff -a

This will remove all swap from the system, move any useful data to RAM and then prevent the system from using it.

This, of course, comes with consequences but that will become evident if you don't have enough RAM.

Answer 2

1. if you want to "make linux stop using swap" You can change the swapiness

sysctl vm.swappiness=0

There are some great explanations here: https://askubuntu.com/questions/103915/how-do-i-configure-swappiness

2.move contents of swap to ram

I think you can only remove everything from your swap to ram by turning the swap off and then on. https://serverfault.com/questions/110436/linux-how-to-explicitly-unswap-everything-possible

Answer 3

If you really want to stop using swap forever you will have to do 2 things:

1. as root (or sudo) run the command swapoff -a
2. Edit the /etc/fstab file and remove/comment out the line that mounts swap partition on boot.

Without a proper sized swap partition, you will loose the ability to hibernate your computer.

It is better to reduce the use of swap by lowering swappiness to 0.