Re: Ken Thompson interview in IEEE Computer magazine (fwd)
Ian D Romanick (idr@cs.pdx.edu)
Sat, 8 May 1999 11:54:56 -0700 (PDT)
> > What exactly do you mean by parallel? There's pretty much two clean ways to
> > do it. One system has access to the physical disks that hold the filesystem
> > or multiple systems have direct access to the physical disks. NFS/SMB/Coda
> > use the former. Sequent's CFS and the similar product for
> > Digital/Sun/HP/IBM use the latter. In the former you are limited by the
> > performace of the system that has access to the disks. In the latter you
> > are limited only by the speed of the disks and the interconnect (to the
> > disks). I can tell you without even thinking too hard which is faster. :)
>
> How about the 3rd way: a cluster of systems, each having local access
> to their own disks. You are limited only by the speed of the network
> to the systems, and how fast each can talk to its local disk. This is
> how Legion does it, and some other parallel filesystems built on top
> of things like NFS (although CIFS would be better).
So, then what do you do when one of the systems catches fire, falls over,
then sinks into the swamp? Do you lose access to its data, or is the data
some how replicated on the other machines? If there is replication, then
how do you arbitrate access to the replicated versions (to prevent access to
stale data) and how do you handle failover?
--
"Don't waste our bandwidth with cliched catch phrases that were moldy
years ago. Be creative- surely with the plethora of bodily fluids, and
other excereta to draw upon you can come up with something a little more
original" -- Rhias K. Hall (badger@wizards.com)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/