> On Jan 8, 2015, at 7:59 PM, Mark Adams <[email protected]> wrote:
> 
> 
> 
> On Thu, Jan 8, 2015 at 7:04 PM, Barry Smith <[email protected]> wrote:
> 
> > On Jan 8, 2015, at 2:47 PM, Mark Adams <[email protected]> wrote:
> >
> > I have a project that needs to show a plan for moving the the new ORNL 
> > machine SUMMIT
> 
>   Isn't Summit IBM PowerN + Nvidia GPUs with a huge percentage of the 
> available floating point performance only available from the GPUs? Thus 
> utilizing the machine means much more utilizing GPUs than utilizing "threads" 
> on the PowerN?
> 
> No, they have very small grids but lots of parallelism because most of the 
> data is in particles.  like 10K particles per cell.  So we just need to run 
> on the CPU.

  Huhh? I don't think one can just run on the CPU's of this machine. You are 
throwing away 90+ percent of the machine! Did someone in authority tell you it 
is fine to just use the CPUs in this machine? Hell, I need to talk to them :-)


  Barry

>  
> 
> 
> > and I wanted to see if there is any writeup or data with respect to thread 
> > performance in PETSc.
> 
>    We've never run the thread code of PETSc on PowerN (I suspect it would be 
> fairly good but PowerN systems are too expensive to buy to test with :-)).
> 
> Well this is your lucky day!  I should be able to get access to the P9 of 
> SUMMIT :) 

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