Block size: 4kbyte => 4_096 byte => ~ 1_000 u32

*------------*
|            |
|   BLOCK    |
|   4KiB     |
*------------*

Superblock => info about the storage
data blocks bitmap => 
inode bitmap
inodes
data sectors


---


meta 4 kib?

inodes

data blocks 4 kib


VecPackT
  [..][..][..][..][..][..] .. [..]
    \
     \
      *----Pack<T> .as_mut().unpack() -> PackGuard<T> {..}
                                            |
                                            |
                                            *--- when Drop() -> (&mut self).update_inode(&self)?
                                            
                                            
What needed
===========
  - store data type T
  - journal, copy on write (COW) or (ROW)
  
Benefit
=======
  - controlled file numbers (1)
  - controlled ROW, or journal write
  - Object version management
  - faster backup, as single file
  - memory efficiency
  - in-memory, file, or hybrid data storage
  - T conversion
  - self healthcheck
  - controlled storage creation