event_base_loop warning

[Fubukimaru]

Hello,

I'm training a network using Horovod and I'm getting this warning constantly:

[warn] event_base_loop: reentrant invocation.  Only one event_base_loop can run on each event_base at once.

The network trains correctly, but it's a bit annoying. I searched a bit on Internet and it seems that is something related to libev and mpi, any clue?

I'm currently using Horovod version 0.13.11

Thanks!

[alsrgv]

@Fubukimaru, which version of Open MPI are you using? Can you try upgrading to Open MPI 3.1.2?

[Fubukimaru]

Hello @alsrgv,

Thanks for your reply. I was using OpenMPI 3.0.0. OpenMPI 3.1.2 is available in my cluster but I cannot use it, I'll contact the guys from support to be able to use it and then come back to you.

Thanks again!

[Fubukimaru]

It seems I get the same warning with OpenMPI 3.1.2. Any recommendation?

Thanks!

[alsrgv]

@Fubukimaru, I'm not sure what could be the issue. Could you report it in https://github.com/open-mpi/ompi issue tracker?

[Fubukimaru]

I haven't had time for posting the issue, but it seems that I'm not alone:
open-mpi/ompi#1081

[alsrgv]

@Fubukimaru, ah - in that case you can probably avoid it by setting HOROVOD_MPI_THREADS_DISABLE=1 during runtime.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.