Control: reassign -1 openmpi-bin 2.0.2~git.20161225-8 Control: severity -1 important Control: retitle -1 openmpi-bin: default for oversubscription changed
Santiago Vila writes: > Package: src:dune-grid > Version: 2.5.0-1 > Severity: serious > > Dear maintainer: > > I tried to build this package in stretch with "dpkg-buildpackage -A" > (which is what the "Arch: all" autobuilder would do to build it) > but it failed: [...] > Status: FAILED > Output: > > -------------------------------------------------------------------------- > There are not enough slots available in the system to satisfy the > 2 slots > that were requested by the application: > test-yaspgrid-yaspfactory-1d > > Either request fewer slots for your application, or make more > slots available > for use. > > -------------------------------------------------------------------------- This looks like OpenMPI changed its default for oversubscription: it seems to now default to not allowing starting more processes than cores available (cores, not threads even). The man page still documents the `--nooversubscribe` option, though `mpirun --help` shows a `--oversubscribe` option (which is not understood by older versions). Other implementations of `mpirun` (mpich) don't seem to understand this option either, but seem to allow oversubscription by default (like older versions of OpenMPI). So one cannot pass the new option to `mpirun` unconditionally. I think it is a bug in OpenMPI to just change this default; at least there should be a way to control this via an environment variable so one doesn't have to provide OpenMPI-specific options to `mpirun`. Ansgar