Re: Nilfs features

[Dave <dave-/hCUnnzDXf0AvxtiuMwx3w@public.gmane.org>]

On 05/30/09 07:44, Jérôme Poulin wrote:
>     checkpointing before installing (which may by default create a
>     snapshot), and then i'd restart the constant checkpointing after i'd
>     finished the install/restore. Please note, i am not comparing nilfs to
> 
>     zfs, but zfs doesn't have constant cp (i think) but does have the
> 
>     feature i mention, i.e you take snapshots when needed (perhaps via a
>     cron job daily, monthly, weekly)
> 
> I just want to give my though on this one, keeping checkpoints as-is 
> seems ideal to me, in this case you have a very granular way to go back 
> in time, however, what you say is right, when installing a new software 
> for example, it's nice to have a way to get back to it, I guess in this 
> case you would just convert the last checkpoint to snapshot before the 
> installation so you have a time mark of where to rollback (and of course 
> have a steady state which won't go away during the installation), right?

Yes correct. Imagine you're installing a fresh OS on a nilfs formatted 
disk. You'd have 1000+ interemediate checkpoints which would be of no 
use. Temporary suspension until the OS is installed is a real life 
use-case. Your filesystem is in 2 states, either no OS or a full OS state.

Cheers
D