[mvapich-discuss] [SOLVED] pthreads and mvapich?

[Tim Hartley]

> > I'm new to the list and am having a strange problem when running
> > pthreads in an MPI process.  The MPI calls are made safely, i.e. only
> > from the initial process.  The pthreads are just workers.  However, on
> > a multicore system, the pthreads always get scheduled on the same
> > core.  That is, multiple pthreads do not get scheduled on more than
> > one core concurrently.  I'm mainly curious if anyone has run into this
> > before.
>
> It seems like the MVAPICH process affinity feature prevent your process
> from using all cores in the node. Can you try using the following flag
> to disable affinity?
> VIADEV_USE_AFFINITY=0

This solution works, thanks!

Tim