Re: HAMMER update 06-Feb-2008

[Bill Hacker <wbh@xxxxxxxxxxxxx>]

Petr Janda wrote:
> >     I do expect the semi-real-time mirroring technology to be in by
> > mid-year, because that will be directly tied into the UNDO fifo and the
> > UNDO fifo is needed for crash recovery.
>
> Cheers,
> Is it possible at this stage to boot DragonFly kernel off a hammer 
> filesystem ? Maybe it would be a good idea to include UFS/HAMMER option in 
> the installer. 
>
> Petr

I'd be very opposed to even *trying* to make HAMMER fs a place from 
which to boot.

Booting in particular, and keeping an OS and core utils 'happy' in 
general (logs aside), are read-mostly-write-seldom creatures.

HAMMER fs, or any other 'feature rich' fs (ZFS et al) need a fully 
operational OS to run them properly.

Yes - these things have been, and are being done.

But it has no advantage anyone has ever been able to explain to me.
Especially when all that is needed to separate 'church and state' is a 
boot device/slice/partition suited to the basic boot and OS needs.

And myriad disadvantages.

Difficulty to do remote maintenance in particular.

JM2CW

Bill