MySQL Low Memory Gotcha

When installing MySQL Client/Server on Ubuntu, if the system has low memory (< 1GB including swap), the installation can silently fail and MySQL Server will never sucessfully start.

This can be remedied by adding (or increasing) the size of swap.

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Check Swap Information

The following command will print swap info as seen below.

$ sudo swapon --show

This shows that there is a 2G swapfile on the system. If there is no swapfile one should be created to fix this issue as well as for general system responsiveness.

NAME		TYPE	SIZE	USED	PRIO
/swapfile	file	2G		195.6M	-1

Create a Swap File

Allocate a new 2G file to use as a swap with the proper permissions.

$ sudo fallocate -l 2G /swapfile
$ sudo chmod 600 /swapfile

Enable the swap file

$ sudo mkswap /swapfile
$ sudo swapon /swapfile

Make the Swap File Permanent

Add the following line to the bottom of your /etc/fstab (or file systems table)

/swapfile	none	swap	sw	0	0

This page is based on this DigitalOcean Article. Please see this link for much more information about swaps in general.