Regarding Filesystems

[Adam Emanuel]

Hello Sir,

Excuse me if my questions was some how stupid.

As I was following, DragonFlyBSD got a the new HAMMER FS. some
questions pushed up my head stack.
If I ain't wasting your time, can u please answer my cents.

1- I know that UFS divides the disk into cylinder group, does this has
anything to do with disk's physical cylinders, let's say they are the
same thing ?

2- In Journaling FS, does the jornal logs all the meda-data itself, or
just the operations to be performed on them,
like DELETE INODE 800 ?

3- What is actually the different between a snapshot and revision (i
know that some file system supports different versions of the same
file) ?

4- What do the B-tree actually hold in HAMMER, do they hold the inodes?

5- Why not use VFS-level journaling like FreeBSD gjournal, which works
on any FS ?

6- I read before that block devices are gone from FreeBSD and
DragonFlyBSD, then how the disks are managed which are block devices,
its bit confusing ?

Sorry if I wasted your time for my questions.

Thanks a lot