[openib-general] A few questions about IBMgtSim

[Sven-Arne Reinemo]

Anno Domini 30-06-2006 17:04, Eitan Zahavi wrote:
> Hi Sven,
> 
> Currently there is no way to scale simulation time to real time. 
> The main reason is that the time scale is mixed:
> * OpenSM calculation time is about the same (if you run the simulator on
> remote node)

So this means that the internal operation of OpenSM with the simulator
is identical to its operation with real hardware?

I have done some performance test with IBMgtSim and OpenSM running on
separate machines and to me it looks like there is very little
concurrency between the two processes. I.e. it looks like they spend a
lot of time  waiting for each other. Below are some results from a few
simulation runs, the observed CPU utilization seems quite low. I would
have expected much higher CPU load for IBMgtSim...  Any thoughts on how
this matches your experience?

OpenSM
#hosts² #sw #ports elapsed¹ kernel¹ user¹ %cpu mem
   288   36     24     585    109   99   35 410
   512   48     32     766    144  136   36 520
  1152   72     48    1161    218  211   36 741

IBMgtSim
#hosts² #sw #ports elapsed¹ kernel¹ user¹ %cpu mem
   288   36     24     586      87   221   52  92
   512   48     32     767     109   278   50 102
  1152   72     48    1161     169   432   51 132

¹time in seconds
²organized in a 3 stage Clos

Best regards,
Sven-Arne

-- 
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