cluster frustrations (Suggestions for same)

[Robert G. Brown]

On Thu, 17 Jan 2002, Greg Lindahl wrote:

> On Thu, Jan 17, 2002 at 11:29:05AM -0500, Robert G. Brown wrote:
> 
> > I totally agree with Mark here -- I can buy somewhere between 2 and 4
> > ECC-memory-equipped nodes over the counter from Intrex (my local vanilla
> > PC supplier) for the cost of one server-class node of equivalent power
> 
> One of the biggest sources of needless arguments on this list is
> different definitions. Since when is the node you described first not
> a "server-class node"?
> 
> If you define "server-class" as "stuff from vendors with huge markups"
> then sure, white boxes usable as servers are going to be cheaper. But
> if you define "server class" as "boxes with certain features, such as
> ECC memory", it's a whole different discussion.
> 
> We get similar discussions over "commodity", "beowulf", "cluster", etc
> etc.

All good points and true.  I certainly didn't want to start a semantic
argument over what is a server class system since you'll get different
answers from nearly anybody you ask depending on what they want to
serve, their tolerance for problems, the features they require (e.g.
hot swap disks or power supplies) and the depth of their pocketbook.

I was actually referencing the ~$2.5K/ea "server class" boxes that were
mentioned (IIRC in my normally somewhat confused mental state;-) in this
very thread.  However, I also generally build my own "servers" for half
that, give or take, depending as you note on detailed features like
SCSI, ECC, amount of disk, local backup device or no.  

With linux especially virtually any OTC system sold down to weenie and
aged Celerons can be a server (and a damn good server at that) to a
small cluster or departmental LAN.  Most of them will simply run for
years flawlessly when turned on and correctly configured.  A few won't.
A high performance cluster (or server) needs to be engineered a bit more
carefully, but the same really holds true there as well.

The point was more "You don't have to spend a fortune to get reliable,
high quality OTC nodes, but you do have to be a smart shopper" than
"server-class (with reference to nodes or otherwise) means anything at
all" to anybody but marketing and management.

Cheerfully corrected,

   rgb

-- 
Robert G. Brown	                       http://www.phy.duke.edu/~rgb/
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb at phy.duke.edu