Ho scoperto pochi giorni fa la soluzione: anche con -m 0 ext spreca vari Gb,bisogna usare l'opzione -T largefile o smili,che vanno a modificare alcune impostazioni sprecone di default.
Codice:
[root@myhost xxx]# mke2fs -T largefile -j -m 0 /dev/sda5
mke2fs 1.41.14 (22-Dec-2010)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
231680 inodes, 59308593 blocks
0 blocks (0.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=0
1810 block groups
32768 blocks per group, 32768 fragments per group
128 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 25 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
Ora non ho una foto,ma risultavano "occupati" solo 200-300 mb (in linea con altri Fs) contro i 2-3 delle impostazioni standard.