[Beowulf] Improving access to a Linux beowulf cluster for Windows users

[Kilian CAVALOTTI]

On Wednesday 09 April 2008 11:48:19 am Greg Lindahl wrote:
> p.s. did anyone see this blog posting claiming that it takes Linux
> clusters several minutes to start a 2048 core job?
>
> http://terboven.spaces.live.com/Blog/cns!EA3D3C756483FECB!267.entry
>
> I would have commented, but you have to have a Microsoft ID to
> comment.

That's a pretty amusing blog, actually. See
http://terboven.spaces.live.com/blog/cns!EA3D3C756483FECB!255.entry 
(wonderful permalinks, btw).

The same benchmark on lower-end hardware (E5345) running Linux (same 4X 
DDR IB though), gives roughly 30% better results:

#---------------------------------------------------
# Benchmarking PingPong
# #processes = 2
#---------------------------------------------------
       #bytes #repetitions      t[usec]   Mbytes/sec
            0         1000         4.72         0.00
            1         1000         4.68         0.20
            2         1000         4.64         0.41
            4         1000         4.74         0.81
            8         1000         4.68         1.63
           16         1000         4.78         3.19
           32         1000         4.79         6.37
           64         1000         4.84        12.61
          128         1000         6.12        19.95
          256         1000         6.47        37.71
          512         1000         7.14        68.40
         1024         1000         8.53       114.54
         2048         1000        10.81       180.65
         4096         1000        14.12       276.58
         8192         1000        20.99       372.21

Graph at: http://tinyurl.com/4ndg9v

Note that latency scaling is much more linear, too. So much for Windows 
better performance and lower latency, huh?

Cheers,
-- 
Kilian