[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