[MITgcm-support] FW: R1 code

[Ed Hill]

Hi Sophie,

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email.  Since you're now subscribed, your emails should go through
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Ed

===

Hello,

My name is Sophie RICCI. I work as a post doc at JPL with Ichiro
Fukumori. I work with your MITgcm code, the version I have is 2 years
old, named R1. Dimitris Menemenlis  who also works in the team
downloaded the latest version recently.

I noticed on the 2 years old version that there are tiles boundaries 
problems when you change the number of processors.  Please find attached
as ps1.ps the difference of rms between 2 runs ( one on 64 and the other
on 32 CPU) for a 60 days period.  Have you seen this problem before? Has
it been corrected in the latest version of the code?

Trying to answer this question myself I switched to the latest version
of the code.  It appears that this tiles boundaries problem is not
visible anymore ( see ps2 that computes the rms difference between 64
and 32 CPU runs for the new version of code).

My problem is that the comparison between old 64 processors and new 64
processors version show pretty big differences ( see ps3 that computes
rms  diff between old and new 64 proc. runs).  Before eventually
switching to the new version of the code I would like to understand
where this differences come from and what are the major changes that
occurred on the code between the 2 versions I have.

Best regards,
Sophie RICCI


>---------------------------------------------------------------------------------------------------------------------
>Sophie RICCI
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>Pasadena, CA 91109-8099, USA    email : sricci at pacific.jpl.nasa.gov
>--------------------------------------------------------------------------------------------------------------------

-- 
Edward H. Hill III, PhD
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