vdioptimize

#!/bin/bash

echo ======== INITIALIZATION ========
if ! [ -f "$1" ]
then
	echo This file doesn\'t exists
	exit
fi
before=$(du -h "$1")
sudo modprobe nbd
echo
sleep 1

echo ======== MOUNTING VIRTUAL DISK ========
slot=0
error=0
while [ "$error" == "0" ]
do
	slot=$(($slot+1))
	if ! [ -b "/dev/nbd$slot" ]
	then
		echo No NBD slot available
		exit
	fi
	lsblk /dev/nbd$slot > /dev/null
	error=$?
done
echo Using /dev/nbd$slot
sudo qemu-nbd -c /dev/nbd$slot "$1"
echo
sleep 1

echo ======== CHECKING /dev/nbd$slot ========
echo \(This will fail if you have a partition table\)
sudo fsck /dev/nbd$slot
sudo e2fsck -yfv /dev/nbd$slot
echo
sleep 1

echo ======== ZEROING /dev/nbd$slot ========
echo \(This will fail if you have a partition table\)
sudo zerofree -v /dev/nbd$slot
echo
sleep 1

for part in /dev/nbd$slot\p*
do
	echo ======== CHECKING $part ========
	sudo fsck $part
	sudo e2fsck -yfv $part
	echo
	sleep 1
	
	echo ======== ZEROING $part ========
	sudo zerofree -v $part
	echo
	sleep 1
done

echo ======== UNMOUNTING VIRTUAL DISK ========
sudo qemu-nbd -d /dev/nbd$slot
echo
sleep 1

echo ======== COMPACTING VIRTUAL DISK ========
vboxmanage modifymedium --compact "$1"
echo
sleep 1

echo ======== BEFORE-AFTER COMPARISON ========
after=$(du -h "$1")
echo $before
echo $after