Swap space notes

Whats using swap space

for file in /proc/*/status ; do awk '/VmSwap|Name/{printf $2 " " $3}END{ print ""}' $file; done | sort -k 2 -n -r | less

Who is eating all of my RAM?

ps aux --sort=-%mem | head

Where are my swap files

 cat /proc/swaps

How to add more swap space

1. Create empty file:
This file will contain virtual memory contents so make file big enough for your needs. This one will create 1Gb file which means +1Gb swap space for your system:

dd if=/dev/zero of=/media/fasthdd/swapfile.img bs=1024 count=1M

If you want to make 3Gb file then change count value to count=3M. See man dd for more information.

2. Bake swap file:
Following command is going to make “swap filesystem” inside your fresh swap file.

mkswap /media/fasthdd/swapfile.img

3. Bring up on boot:
To make sure that your new swap space is activated while booting up computer you should add it to filesystem configuration file /etc/fstab. Add it to end of file, this is recommended because other filesystems (at least one that contains swap file) must be mounted in read-write mode before we can access any files.

# Add this line to /etc/fstab
/media/fasthdd/swapfile.img swap swap sw 0 0

4. Activate:
You can either reboot your computer or activate new swap file by hand with following command:

swapon /media/fasthdd/swapfile.img

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