[Dovecot] Best inode_ratio for maildir++ on ext4

[Rodolfo Gonzalez]

Hi,

This might be a silly question: which would be
the best inode ratio for a 5 Tb filesystem dedicated to Maildir++
storage? I use ubuntu server, which has a preconfigured setting for
mkfs.ext4 called "news" with inode_ratio = 4096, and after formating the
fs with that setting and then with the defautl setting I see this
difference of space (wasted space, but more inodes):

4328633696 free 1K-blocks with mkfs's "-T news" switch = 1219493877 free
inodes
4557288800 free 1K-blocks with default mkfs settings = 304873461 free inodes

I'll be storing e-mail messages for around 20,000 accounts on that 
partition (average 512 Mb per account). Would you consider worth the 
waste of about 200 Gb of the filesystem space in exchange of more inodes?

Thanks.
Rodolfo.