Hi Daniel, We are actually working on this at the moment. There is a ticket to describe the status of the work: https://trac.mpich.org/projects/mpich/ticket/79. Despite the appearance, there is work planned here. Currently, this is slated for MPICH 3.3 in 2016. It’s possible that it could show up earlier in the nightlies, but there’s no guarantees. Thanks, Wesley On Dec 9, 2014, at 1:17 PM, Daniel Ibanez <[email protected]<mailto:[email protected]>> wrote: Hello, I have noticed that simple things like MPI_Barrier will raise my CPU usage to near 100% while waiting, and read in past emails and the FAQ that this is due to busy polling in Nemesis. As far as I can tell, the one solution usually offered to reduce this CPU usage is reconfiguring with sockets instead of Nemesis. I would also like to use the MPI_THREAD_MULTIPLE feature, but I read that the socket channels don't support it, and it would be annoying to have to recompile MPICH to get one benefit or the other. I was just wondering if recent advancements invalidated some of the above and officially ask what the options are for reducing the CPU usage of MPICH during barriers. Thank you, _______________________________________________ discuss mailing list [email protected]<mailto:[email protected]> To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss