Linux SwapFile Overview

Linux RAM is composed of chunks of memory called pages. To free up pages of RAM, a linux swap can occur and a page of memory is copied from the RAM to pre-configured space on the hard disk. Linux swaps allow a system to harness more memory than was originally physically available.

However, swapping does have disadvantages. Because hard disks have a much slower memory than RAM, virtual private server performance may slow down considerably. Additionally, swap thrashing can begin to take place if the system gets swamped from too many files being swapped in and out.

Check Swap Usage

Before we proceed to set up a swap file, we need to check if any swap files have been enabled on the VPS by looking at the summary of swap usage.

swapon -s

 

Create Swap File 1GB

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


Make Swap File As Swap Device

mkswap /swapfile

 

Make Swap Automount

nano /etc/fstab/swapfile       none    swap    sw      0       0

 

Start mount Swap

swapon -a