[Beowulf] What services do you run on your cluster nodes?

[Håkon Bugge]

At 02:54 23.09.2008, Perry E. Metzger wrote:

>By the way, if you really can't afford for things to "go away" for
>1/250th of a second very often, I have horrible news for you: NO
>COMPUTER WILL WORK FOR YOU.

Obviously a statement from someone not on the top 
of the subject. Here, a statement from someone 
who is. Snip from 
[http://domino.research.ibm.com/comm/research_projects.nsf/pages/osjitter.index.html]:

"Jones et al. [2] found that with only 0.31% 
daemon and OS activity on each CPU of a dedicated 
4096 processor IBM SP system, MPI_Allreduce operation degraded more than 400%"

So Perry, some reading may be? Let me suggest 
“The Case of the Missing Supercomputer 
Performance: Achieving Optimal Performance on the 
8,192 Processors of ASCI Q,” in ACM/IEEE 
Conference on Supercomputing (SC’03), (Phoenix, Arizona, USA), Nov. 2003.

Then, you can comment on your own statement above written using caps locks ;-)



Håkon