do concurrent in parallel? speed-up?

[Tim Prince]

On 2/11/2014 11:34 AM, Anton Shterenlikht wrote:
> Hello
>
> How can I get speed-up from using
> DO CONCURRENT with gfortran 4.8/4.9?
> I can run a do concurrent program,
> but it seems to only use one CPU,
> and gives no speed-up.
> Are there any special compiler flags?
>
> Thanks
>
> Anton
>
In principle, do concurrent might work to some extent with 
auto-parallelization flags, but even with ifort, that isn't as effective 
as turning it into an f77 DO loop and applying OpenMP.

I've turned my masked do concurrents into DO loops with MERGE for the 
benefit of gfortran 4.9.  ifort needs VECTOR ALIGNED directives to get 
full performance of masked DO CONCURRENT, and it's still fully effective 
only for single thread vectorization.

-- 
Tim Prince