[Starpu-devel] Online Performance Monitoring With Performance Models in Fortran StarPU

[Marcelo Cogo Miletto <marcelo.miletto@inf.ufrgs.br>]

Dear StarPU team,

I have been trying, without success, to use a performance model for
online performance monitoring in a Fortran application that uses
StarPU (release 1.3.7) to use data-aware schedulers. The best result I
got so far was an empty model being dumped in the
$STAPU_HOME/.starpu/sampling/codelets/45.

I tried to include functions in the src/util/fstarpu.c and in
include/fstarpu_mod.F90, to allocate and configure the performance
model, assigning it to a codelet in a very similar way to how the task
codelet structure creation and configuration is done in the Fortran
examples (e.g., using fstarpu_codelet_allocate, fstarpu_codelet_set_name).

I use a c_ptr type variable in Fortran that should hold the performance
model structure address. Then, I set its symbol and its type to
STARPU_HISTORY_BASED,  initialize it by calling starpu_perfmodel_init, and
assign it to the codelet structure using cl->model = &my_model, all
this with the functions abovementioned.

Other things that I have considered:
 - STARPU_CALIBRATE set to 1
 - STARPU_SCHED set to dmda
 - Application calls fstarpu_init
 - Application calls fstarpu_shutdown

The performance model dumped file reports that model->state->ncombs is
0, so it does not print anything after the file header:

##################
# Performance Model Version
45

####################
# COMBs
# number of combinations
0

At this point, I'm a little bit lost on where the problem is. As I'm
not very acquainted with Fortran, I wonder if this is the right path
to use such models in a StarPU Fortran application. Also, I would find
helpful if you have some minimal code example on how to do it properly
to share with me.

Best,
Marcelo Miletto.