[netcdfgroup] netCDF Operators NCO version 5.0.1 are liberated

• To: NCO Announce Mail List <nco-announce@xxxxxxxxxxxxxxxxxxxxx>, netcdfgroup@xxxxxxxxxxxxxxxx
• Subject: [netcdfgroup] netCDF Operators NCO version 5.0.1 are liberated
• From: Charlie Zender <zender@xxxxxxx>
• Date: Tue, 13 Jul 2021 14:55:39 -0700

The netCDF Operators NCO version 5.0.1 have arrived.

http://nco.sf.net (Homepage, Mailing lists, Help)
http://github.com/nco (Source Code, Issues, Releases, Developers)

What's new?
Version 5.0.1 contains the necessary options for ncremap to exploit
MPI-enabled weight generators such as ESMF_RegridWeightGen.
You can probably skip this release unless you use ncremap.

Work on NCO 5.0.2 has commenced and and it targeted to offer ncremap
support for the MOAB offline regridding package mbtempest.

Enjoy,
Charlie

NEW FEATURES (full details always in ChangeLog):

A. ncremap accepts two new and related options, mpi_pfx and mpi_nbr.
  The --mpi_pfx=mpi_pfx option specifies an appropriate job
  scheduler prefix for MPI-enabled weight-generation
  executables such as ESMF's ESMF_RegridWeightGen and MoabTempest's
  mbtempest. Other weight generators (ncks, GenerateOfflineMap)
  are unaffected by this option since they are not MPI-enabled.
  mpi_pfx defaults to mpirun -n $mpi_nbr on all machines except those
  whose $HOSTNAME matches an internal database of DOE-operated
  supercomputers where mpi_pfx defaults to srun -n $mpi_nbr.
  When invoking --mpi_pfx, be sure to explicitly define the
  number of MPI tasks-per-node, e.g.,

  ncremap --mpi_pfx='srun -n 16' ...
  ncremap --mpi_pfx='srun --mpi=pmi2 -n 4' ...

  The separate --mpi_nbr=mpi_nbr option specifies the
  number of tasks-per-node that MPI-enabled weight generators
  will request. It preserves the default job scheduler prefix (srun or
  mpirun):

  ncremap --mpi_nbr=4 ... # 16 MPI tasks-per-node for ERWG/mbtempest
  ncremap --mpi_nbr=16 ... # 4 MPI tasks-per-node for ERWG/mbtempest

  Thus --mpi_nbr=mpi_nbr can be used to create host-independent ncremap
  commands to facilitate benchmarking the scaling of weight-generators
  across hosts that work with the default value of mpi_pfx.
  The --mpi_pfx option will prevail and --mpi_nbr will be ignored if
  both are used in the same ncremap invocation. Note that mpi_pfx is
  only used internally by ncremap to exploit the MPI capabilities of
  select weight-generators. It is not used to control and does not
  affect the distribution of multiple ncremap commands among a cluster
  of nodes.
  http://nco.sf.net/nco.html#mpi_pfx
  http://nco.sf.net/nco.html#mpi_nbr

BUG FIXES:

A. No bug fixes this release

Full release statement at http://nco.sf.net/ANNOUNCE
--
Charlie Zender, Earth System Sci. & Computer Sci.
University of California, Irvine 949-891-2429 )'(