[Beowulf] How Can Microsoft's HPC Server Succeed?

[Mark Hahn]

> damage?  Presumably you have decent file system protection so that user A 
> can't do bad things (or even see) user B's files.  All that happens is bad 
> guy User A zaps their own stuff.

this assumes that the windows admin knows enough not to ever run anything 
untrusted, or perhaps he's set up some fileservers/trees as readonly,
or that users are not permitted to load their own executables, etc.
I suspect that these things, which would be natural to any *nix admin,
are not exactly second-nature to windows admins.  (disclaimer: I don't 
know any serious windows admins.)

> Sure.. you let your cluster issue outbound network traffic to the big wide 
> internet?  This is probably harder to actually allow than to prevent.

huh?  I'm guessing the natural windows cluster organization is to put all
the compute nodes on the full corporate/campus network.  it's not as if the 
windows world is really used to separating and tunneling GUIs over networks,
at least not with the same level of naturalness as X and the usual SSH tunnel.

> Most 
> clusters have a "totally inside the cluster" network that's only implicitly 
> bridged to the outside world through the headnode.

most _*nix_ clusters, yes.  but the whole discussion is windows, where users 
will naturally expect their job to see the same environment as their desktop,
same filesystems, same graphics, same network access.

> up the system.  But, also, recall the general model we were discussing.. 
> smallish cluster to support some commercial application (say, a 
> computationally intensive FEM code).

one interesting fact is that the growth in cores of single machines is
actually working _against_ the need for windows clusters.  who wouldn't 
rather just run jobs on a 32-core server, rather than screwing around 
with mpi on a cluster?

> In this scenario, the cluster is 
> basically sort of a "network attached appliance".  There are lots of network 
> attached storage devices out there (e.g. from Maxtor) using some form of 
> Windows as the OS.  They tend not to have AV stuff, just because the software 
> on the appliance is fairly tightly configuration managed (i.e. nobody goes 
> out running random programs on the NAS box).  It's just not a huge threat.

so you really think people will buy a packaged windows compute cluster
preloaded with exactly one CFD code, and never be tempted to install other 
apps on it?  I think that's absurd, at least based on the kinds of things 
I see people doing with clusters.  the tool of the moment is constantly
changing, even if the group isn't actually developing their own tools.

appliances are a very attractive concept, but one that is inherently at war
with the very general-purpose-ness of computers (and clusters).  what _might_
work is to sell the CFD appliance as a _service_...