[Omp] Recursive routines

[Michael Suess]

On Wednesday 06 April 2005 13:57, Patricia Bittencourt Sampaio wrote:
>  Hello,
>
>     I have been trying to write an openmp version of
> some applications. One of them is the recursive
> mergesort. I have not found out a way to parallelize
> the recursive routine of mergesort since the recursive
> mecanism is purelly data dependent.
>
>     So, I conclude that a recursive routine can't be
> parallelized with openmp so as to run the application
> faster. Instead, it's necessary to convert this
> routine for an iterative routine so as to be able to
> use the directives of openmp more effective.
>     Maybe for some other applications with a recursive
> routine where more work has to be done on it, it
> becames worth to parallelize a code inside the
> recursive routine, but that is not the case for
> mergesort.
>     I'd like to know your experiences with a recursive
> routine using openmp...

I have been experimenting with a recursive version of quicksort and OpenMP, 
and I have put down my experiences here:
http://www.plm.eecs.uni-kassel.de/plm/fileadmin/pm/publications/suess/sortOpenMP.pdf

The source code to the programs described there is available from the OpenMP 
Source Code Repository:
http://www.pcg.ull.es/ompscr/

Best regards,
Michael