[Beowulf] network filesystem

[Chris Samuel]

On Mon, 5 Mar 2007, Mark Hahn wrote:

> why V4?
> - security.  within a cluster, I don't see the point to, say, kerberos.

Agreed, not to mention all the pain of trying to get Kerberos tickets passed 
through the queueing system and the fact that if you're running a 3 month job 
it's going to be quite hard to persuade your Kerberos admin to let you be 
able to create a ticket that lasts that long..

> - compound rpcs.  probably provides somewhat better efficiency.

Yup, should ease the burden of a lot stat()'s.

> - open/close, byte-range locking.  I don't see much demand.

Pass. :-)

> - client caching/delegation/leases - could be valuable for efficiency.

Indeed, this to me is the most useful part of it, especially for those people 
who are running code that should use local scratch but doesn't (either due to 
lack of coding experience or not having access to the source)..

> I find that nfsv3 works fine for moderate IO on O(100) clients.

Likewise, though we do get the occasional user who is able to generate a 
pathological case..

> I would be very interested to know whether others have observed
> performance benefits for v4, and whether it's an easy upgrade,
> such as no new/onerous security framework ('framework' is always
> a danger sign for me ;)

When I last played with it you could still use AUTH_SYS (as in v3) rather than 
having to use Kerberos.

cheers!
Chris
-- 
 Christopher Samuel - (03)9925 4751 - VPAC Deputy Systems Manager
 Victorian Partnership for Advanced Computing http://www.vpac.org/
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