Create loopback filesystem

loopback-fs.sh

# Create a loop-mounted filesystem to allow a very high inode count
# without having to reformat entire partition

# Allocate a 1.5TB file without actually having to write 1.5TB of data
fallocate -l 1500G /path/to/filesystem.img

# Make an ext4 filesystem in this file with:
#   (-i) One inode per 1024 bytes
#   (-F) Force creation of the filesystem even though the
#        file is not a block special device
mkfs.ext4 -F -i 1024 /path/to/filesystem.mg

# Disable journaling for data but leave enabled for metadata
# Protects against filesystem corruption in the event of a crash
# but might leave some file data half written
tune2fs -o journal_data_writeback /path/to/filesystem.img