Fix slow filesystem with logs of Roms/images/videos.

[vykyan]

Hey all, I was having a lot of trouble after copying all my roms,images,videos etc over to the Pi. It would take forever to read/write to the filesystem because of the amount of files.

After copying all my roms/images/videos, apt-get update would take about 20 minutes, and forget apt-get upgrade (166mb of updates took about an hour, and it only got to the 7th update).

So i've come up with a solution that makes it as quick as a new install! :D

(for my 128gb card)

set reserved space to 0% on root ;

sudo tune2fs -m 0 /dev/mmcblk0p2 )

Shrink root to ~9gb. (Use other Linux system (Gparted LiveCD) to shrink it, Keep it EXT4)
create a new partition in the rest of the space (~119gb)
format new partition in BTRFS
mount new BTRFS partition as /home/pi/btrfsDrive in FSTAB;

/dev/mmcblk0p3 /home/pi/btrfsDrive btrfs defaults 0 1

chown it to pi:pi

sudo chown pi:pi -R /home/pi/btrfsDrive

copy all roms/images/videos to /home/pi/btrfsDrive

then BIND mount all the folders in /home/pi/btrfsDrive in FSTAB

/home/pi/btrfsDrive/BIOS /home/pi/RetroPie/BIOS none bind 0 0
/home/pi/btrfsDrive/downloaded_images /opt/retropie/configs/all/emulationstation/downloaded_images none bind 0 0
/home/pi/btrfsDrive/roms /home/pi/RetroPie/roms none bind 0 0

Then either restart or;

sudo mount -a

Now I don't get any Filesystem slowdown/lag with a nearly full 128gb card with the same amount of files as my previous EXT4 setup.