[MITgcm-devel] global sum

[Martin Losch]

Hi there,

I didn't follow the development of the global-sum code. Under which circumstances should I use which of these variants:
_GLOBAL_SUM (as, e.g., in seaice_lsr for the residuals)
call global_sum_tile
call global_sum_single_cpu

Currently, I would like to figure out if I can actually fix the multithreading of the file seaice_fgmres.F
In there I use "stolen" code, which I don't quite know how to handle. In particular there is a scalar product, that I adjusted to use MPI, but now I would like it to use a global-sum variant.

Martin

PS. Related to this file, should I actually use LAPACK routines (actually BLAS), if HAVE_LAPACK is defined?