LensPix: not working for very high lmax?

[Matteo Calabrese]

Hello All,

I try to use LensPix with high map resolution, such as
Nside = 4096 and lmax = 3*Nside = 12288; however the
program stumbles at the synthesis operation, in particular
at the

Code: Select all

polalm2map

routine.

The problem seems to happen at the final stages of the computation, when the

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MPI_GATHERV

command gathers information processed by the different mpi tasks:
basically the code waits forever for all the MpiId to report back, which will never happen.

The code has been run on a cluster with 10 nodes, 80 Mpi tasks in total (changing these numbers does not affect the result: the program still stumbles for nside=4096, lmax=12288).

This problem does NOT occur if nside=2048 and lmax=6144, as the computation in this case is smoothly done.

Has anyone experienced the same problem? Any suggestions to solve it?

Thanks a lot in advance,
Matteo Calabrese

ps. Additional LensPix parameters:
lens_method = 1
interp_factor = 3
interp_method = 1
mpi_division_method = 3
want_pol = T
rand_seed = -1