[Ncep.list.emc.fv3gfs_tickets] FV3GFS Ticket #12: Changes for nests

Rusty Benson - NOAA Federal rusty.benson at noaa.gov
Wed Apr 5 18:12:35 UTC 2017


George,

One suggestion I would make regarding the Cray system is to run the test
case multiple times and compare the data to verify run-to-run
reproducibility.  With some of the advanced Intel compiler options, you can
lose the guarantee of run-to-run reproducibility - especially when the
advanced vector instruction sets are in use and dynamic memory alignment is
enabled.

Rusty
--
Rusty Benson, PhD
Modeling Systems Group
NOAA Geophysical Fluid Dynamics Lab
Princeton, NJ

On Wed, Apr 5, 2017 at 1:07 PM, FV3GFS Trac Ticket <
ncep.list.emc.fv3gfs_tickets at noaa.gov> wrote:

> #12: Changes for nests
> --------------------------+----------------------------
>   Reporter:  tom.black@…  |      Owner:  george.gayno@…
>       Type:  enhancement  |     Status:  accepted
>   Priority:  major        |  Milestone:
>  Component:  component1   |    Version:
> Resolution:               |   Keywords:  nest
> --------------------------+----------------------------
>
> Comment (by george.gayno@…):
>
>  As mentioned in comment:8, the build on Theia uses "-O3" and on Cray uses
>  "-O0".  I used Grads to view the output orography files created on each
>  machine.  I only checked tiles 1 and 7.  And only the 'rlat', 'rlon',
>  'slmsk', 'land_frac', 'orog_filt' and 'orog_raw' records.
>
>  For tile 1, only the 'land_frac' record was different.  Only one point was
>  different.  This difference was 'floating point'.
>
>  For tile 7 (the nest), the 'land_frac' record had differences between
>  -.002 and -.001.  The 'orog_raw' and 'orog_filt' records had differences
>  between -1.5 and 0.9.  All differences were confined to a single column in
>  the middle of the grid.
>
> --
> Ticket URL: <https://svnemc.ncep.noaa.gov/trac/fv3gfs/ticket/12#comment:11
> >
> fv3gfs <https://svnemc.ncep.noaa.gov/trac/fv3gfs>
> NGGPS FV3GFS Development
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.lstsrv.ncep.noaa.gov/pipermail/ncep.list.emc.fv3gfs_tickets/attachments/20170405/83827efe/attachment.html 


More information about the Ncep.list.emc.fv3gfs_tickets mailing list