Transition to ESMF 5

Why ESMF-5?

• Version 5.2.0rp2 is the last public release from the ESMF core team
• More stable interfaces (standardization)
• Better performance
• Supports faster regridding (Ben’s testing)
• Conservative regridding
• Interoperability with other modeling groups
• Native methods for I/O methods for Fields and FieldBundles (read and write netCDF in parallel)
• Internal releases (6.1.0 released in November, 6.1.1 January 2013, 6.2.0 coming soon): no code changes are required!
• Next public release anticipated in the fall of 2013

Changes Between ESMF-4.0.0rp2 and ESMF-5.2.0.rp2

• Interface Changes between ESMF-4.0.0rp2 and ESMF-5.0.0
• Interface Changes between ESMF-5.0.0 and ESMF-5.1.0
• Interface Changes between ESMF-5.1.0 and ESMF-5.2.0 (PDF)
• Interface Changes between ESMF-5.1.0 and ESMF-5.2.0 (PDF)
• Interface Changes between ESMF-5.2.0 and ESMF-5.2.0r (PDF)
• Interface Changes between ESMF-5.2.0r and ESMF-5.2.0rp1 (PDF)
• There were no Interface Changes between ESMF-5.2.0rp1 and ESMF-5.2.0rp2

Key Differences

• use ESMF_Mod -> use ESMF

ESMF_Mod.png

• keyword arguments are now required for all optional arguments

ESMF_Keywords.png

• Argument name changes

• Ordering of items in container classes (ESMF_State and ESMF_FieldBundle)

Important Interface Changes

• ESMF_Initialize
  • Add logKindFlag=ESMF_LOGKIND_NONE

ESMF_Logging.png

• ESMF_GridCompSetEntryPoint (and MAPL_GridCompSetEntryPoint):
  • ESMF_SETINIT -> ESMF_METHOD_INITIALIZE
  • ESMF_SETRUN -> ESMF_METHOD_RUN
  • ESMF_SETFINAL -> ESMF_METHOD_FINALIZE

ESMF_SETRUN.png

• ESMF_StateAdd
• ESMF_FieldBundleAdd
  • Both calls now require a list (vector!) of fields, or fieldBundles.

ESMF_StateAdd.png

We suggest to use MAPL wrappers:

• MAPL_StateAdd
• MAPL_FieldBundleAdd

FieldBundleAdd.png

Status of the Transition

• Ganymed-3_0 just released
  • Zero diffs for restarts and history output
  • Ability to read/write netCDF restarts
  • Switch to MVAPICH2 (from Intel MPI 3)
  • Switch to Intel 13 real soon
  • Note that the order of variable in netCDF output in now alphabetical and comparison with previous output is more involved

• SI team plans to convert:
  • DAS
  • Coupled Model
  • MAPL Tutorials

Known Issues

• Better garbage collection by VM_Finalize
• This might cause crashes inside ESMF_Finalize
• Workaround: call MPI_Finalize instead

Summary

• Do not rely on order inside ESMF_State or ESMF_FieldBundle

• Make use of MAPL

• If you have issues with converting your code, see any SI team member

Category:SI Team Category:Brown Bags