partial barrier

[Allan Ma]

Hi,

I'm a bit new to using mpi. Just wondering if there's a way to implement a partial barrier between synchronously started mpi process like:

mpirun -n 8 python train.py

I want to put a comm.Barrier() at a certain part during training and only odd rank number of those processes got blocked there.

Thanks in advance.

Cheers

[Lisandro Dalcin]

This is not an issue, these kind of users questions should be posted in our mailing list https://groups.google.com/forum/#!forum/mpi4py

In order to implement a partial barrier, you need to create subcommunicators, e.g. by using subcomm = comm.Split(comm.rank%2).

[Allan Ma]

Awesome, thanks for the help. I'm make sure I post to the mailing list next time.