Create a RAM Disk (tmpfs) in Raspberry Pi 3

“tmpfs” writes to RAM instead of the SD card on the Raspberry Pi. It is very easy to use, fast, and avoid writing too much on the SD card. Excessive writing to the SD card will break it easily. Please remember that all data on that RAM Disk will be lost after reboot.

Setup Procedures (Please use root)

Create the temporary directory for the RAM Disk.

mkdir /var/tmp

Edit the fstab file using your favourite editor (e.g. vi)

vi /etc/fstab

Add the following line to /etc/fstab to create a 400MB RAM Disk

tmpfs /var/tmp tmpfs nodev,nosuid,size=400M 0 0

Execute the following command to mount the newly created RAM Disk

mount -a

To verify the RAM Disk is created and mounted successfully, execute the following command

df -h

and you should see something like this

Filesystem      Size  Used Avail Use% Mounted on
/dev/root        29G  1.5G   26G   6% /
devtmpfs        458M     0  458M   0% /dev
tmpfs           462M     0  462M   0% /dev/shm
tmpfs           462M  6.2M  456M   2% /run
tmpfs           5.0M  4.0K  5.0M   1% /run/lock
tmpfs           462M     0  462M   0% /sys/fs/cgroup
tmpfs           400M     0  400M   0% /var/tmp
/dev/mmcblk0p1   63M   22M   42M  35% /boot

Temporary files can now be write to /var/tmp partition. This blog will share more use cases on this RAM Disk.