Jeffrey J. Kosowsky wrote:
>
> > Collisions aren't quite the point - you have to manage that anyway. The
> > hard part is knowing that the final target you link to is the one that
> > you wanted, not a something created simultaneously by a different
> > process doing the same computations, and knowing that the count of
> > existing links always matches the actual copies. The kernel manages
> > this automatically when using links. If you have to add an extra system
> > call to lock/unlock around some other operation you'll triple the overhead.
>
> I'm not sure how you definitively get to the number "triple". Maybe
> more maybe less.
Ummm, link(), vs. lock(),link(),unlock() equivalents, looks like 3x the
operations to me - and at least the lock/unlock parts have to involve
system calls even if you convert the link operation to something else.
> Les - I'm really not sure why you seem so intent on picking apart a
> database approach.
I'm not. I'm encouraging you to show that something more than black
magic is involved. Databases sort-of work for some things. They aren't
particularly better at storing files than a filesystem. If they were,
we wouldn't use filesystems for anything. You've made a bunch of claims
about how a database might be better, but so far have not provided any
evidence to back it up.
> I can understand someone arguing that it would take
> too much effort to implement but I don't see the point of challenging
> the workability of a database approach, particularly when most high
> end enterprise backup systems do just exactly that (and for good
> reason!).
One of the 'good reasons' is that most of those systems were designed
for an OS that didn't have a decent filesystem at the time...
--
Les Mikesell
lesmikes...@gmail.com
------------------------------------------------------------------------------
OpenSolaris 2009.06 is a cutting edge operating system for enterprises
looking to deploy the next generation of Solaris that includes the latest
innovations from Sun and the OpenSource community. Download a copy and
enjoy capabilities such as Networking, Storage and Virtualization.
Go to: http://p.sf.net/sfu/opensolaris-get
_______________________________________________
BackupPC-users mailing list
BackupPC-users@lists.sourceforge.net
List: https://lists.sourceforge.net/lists/listinfo/backuppc-users
Wiki: http://backuppc.wiki.sourceforge.net
Project: http://backuppc.sourceforge.net/
