[MITgcm-support] problems at tile bdys?

[Jean-Michel Campin]

Hi Yuan,

Could you proceed with the same recommendation (sending tar file of dir with 
modified/customized source file and all data* files for this set-up)
or is there too much source-code involved ?

If we are lucky, it could be the same Pb and then will be easier to identify 
with 2 set-up (instead of just 1). Otherwise, might have 2 separate Pb to fix ...

Cheers,
Jean-Michel

On Sun, Jun 16, 2013 at 09:35:08PM -0700, Yuan Lian wrote:
> Hi Jean-Michel,
> 
> I found the similar behavior of MITgcm when there are multiple tiles in x direction. The issue is particularly obvious when active tracers are enabled, e.g. water cycle, where I can see the periodical oscillation of tracers including temperature at the boundaries between the tiles. The problem is less apparent in y direction. I am wondering if it has something to do with exchange routines in x direction. The simulations are done in 3d channel. Thanks.
> 
> Best,
> Yuan 
> 
> Jean-Michel Campin <jmc at ocean.mit.edu> wrote:
> 
> >Hi Jody,
> >
> >Could you send (in a tar file) the directory that contains all the 
> >modified/customized files you are using (the argument of "genmake2
> >-mods" command)
> >as well as all the parameter files (all data* files) for this set-up ?
> >Also, if you are not using the latest version of MITgcm code, which
> >version 
> >(checkpointXYz ? or time of the latest "cvs update") are you using ?
> >
> >It's possible that we can find the problem like this; otherwise, will
> >have 
> >to try to reproduce it (and in this case will also need the binary
> >input files).
> >
> >Cheers,
> >Jean-Michel
> >
> >On Sat, Jun 15, 2013 at 11:03:30PM -0700, Jody Klymak wrote:
> >> 
> >> Hi All,
> >> 
> >> I ran a simulation in a 2-D channel but three-D in setup, and all ran
> >fine.  Well except it stayed 2-D because there was nothing to cause
> >there to be spanwise motion.  The simulations are nonhydrostatic.  
> >> 
> >> So, I added a very small amount of three d by a few different
> >methods, and everytime, no matter how I set up the three dimensionality
> >(bottom roughness, initial velocities, surface displacements) there
> >would an instability at the same spot in x.  It turns out it is a tile
> >boundary in the middle of the domain.  
> >> 
> >> I'm using advection scheme 33, and chnaged OLx and OLy to 5, but
> >still the same problem.  I tried a few other advection schemes, with
> >the same issue (it happens in a hundred or so timesteps, so its easy to
> >debug, at least).  I also tried upping the iterations on the CG3d
> >solver, but that didn't help at all.
> >> 
> >> I've now gone back to the same setup I started with, but changed by
> >tile layout (half as many tiles), and the instability is gone.  
> >> 
> >> Has anybody run into this?  Any suggestions for a fix or what to look
> >for?  (I guess the stupid fix is not to use that tile configuration,
> >but that seems flakey).
> >> 
> >> Thanks,   Jody
> >> 
> >> 
> >> --
> >> Jody Klymak    
> >> http://web.uvic.ca/~jklymak/
> >> 
> >> 
> >> 
> >> 
> >> 
> >> _______________________________________________
> >> MITgcm-support mailing list
> >> MITgcm-support at mitgcm.org
> >> http://mitgcm.org/mailman/listinfo/mitgcm-support
> >
> >_______________________________________________
> >MITgcm-support mailing list
> >MITgcm-support at mitgcm.org
> >http://mitgcm.org/mailman/listinfo/mitgcm-support
> 
> -- 
> Sent from my Android phone with K-9 Mail. Please excuse my brevity.

> _______________________________________________
> MITgcm-support mailing list
> MITgcm-support at mitgcm.org
> http://mitgcm.org/mailman/listinfo/mitgcm-support