My PLEX host has RAM, it’s currently a Dell R910 with 256 gigs of ram. I don’t want to murder my twin 1tb SSD’s doing all that fancy transcoding so I have mine use 50 gigs of ram as a temporary folder. You can use much less but I on average with 3 streams going am using less than 20 gigs of ram for the system so I can spare the memory.
Here’s how to accomplish this on Ubuntu.
sudo mkdir /mnt/plexdisk
sudo mount -t tmpfs -o rw,size=50G tmpfs /mnt/plexdisk
verify it’s mounted
before we make it a forever change, make a backup cause one mistake can be bad.
sudo cp -v /etc/fstab /etc/fstab.backup
make it mount on boot
sudo nano /etc/fstab
Add this to the bottom then CTL+X to exit and save
tmpfs /mnt/plexdisk tmpfs rw,size=50G 0 0
Reboot if you want.
Now to the PLEX interface.
Under server settings navigate to Transcoder
Set the Transcoder temporary directory to /mnt/plexdisk
either reboot or just restart the PLEX service
systemctl restart plexmediaserver.service or whatever you called it.