[Mitgcm-support] Re: pkg/seaice and pkg/exf

[mitgcm-support at dev.mitgcm.org]

Hi Dimitris, 

(i) I'd appreciate you writing a pickup_seaice.chkpt file: what use is the
pickup.chkptA file without the seaice fields?  For one, I use these files
routinely.

(ii) It's rather inconvenient for joinpickup not to work with the seaice
pickups. Unless there's a policy to phase out parallel I/O it seems like a
backwards step not to maintain the join utility (or change
seaice_pickup.F). If parallel I/O is to be phased out I'd appreciate a
startup error message that stops the code if seaice is on but singleCpuIO
is off. 

I can work round these problems, but I have to repeat my 3day long
calculation (because I can't pick it up).

Sorry to be fussy, but these conveniences are not unimportant. 
Tom.


On Fri, 14 Feb 2003, Dimitris Menemenlis wrote:

> 
> Hi Tom,
> 
> >> (i) when pickup.chkptA is written, there's no pickup_seaice.chkptA.
> 
> The only time this situation will occur is in the final checkpoint,
> if this happens not to coincide with the chkptFreq
> 
> This is because sea-ice checkpoint is done internally by the sea-ice
> model, and there is no provision for:
> C--   Final checkpoint (incase the in-loop checkpoint was missed)
> 
> That can be changed, if you like.  But it's easier to just specify
> the appropriate chkptFreq and/or pChkptFreq in the data file.
> 
> >> (ii) Also, I get:
> >> 
> >> PGFIO-F-253/unformatted read/unit=9/attempt to read non-existent record
> >> (direct access).
> >>  File name = pickup_seaice.0000026280    unformatted, direct access
> >> record = 1596
> >>  In source file mdsio_readfield.f, at line number 1651
> 
> I have not used joinpickup but my guess is that it would need to be modified
> for pickup_seaice files, since the internal structure is different from that
> of the other pickup files.
> 
> If you use MPI, you can just set:
> 
> globalFiles    = .TRUE.
> useSingleCpuIO = .TRUE.
> 
> in the data file and do the joining on the fly.
> You would be left with a lot fewer files to worry about.
> 
> D.
> 
> -- 
> Dimitris Menemenlis                      menemenlis at jpl.nasa.gov
> Jet Propulsion Lab, MS 300-323           tel: 818-354-1656
> 4800 Oak Grove Dr, Pasadena CA 91109     fax: 818-393-6720
>