Startup
General Startup procedure of the Octopus Code
The flow chart for most calculations has many steps in common, most of them related to setting up the basic data structures of the code.
The ‘main’ program only performs tasks which are independent of the actual calculation and the physical system:
In a strongly simplified way, we have:
program main
[...]
! "constructors": ! start code components
call global_init() ! initialize the mpi, clocks, etc.
call parser_init() ! initialize the input parser
call messages_init() ! initialize the message system
call walltimer_init() ! initialize the timer module
call io_init() ! initialize the I/O subsystem
call calc_mode_par_init() ! initialize parallelization strategy
call profiling_init() ! initialize and start the profiling system
call run(inp_calc_mode) ! pass control to the 'actual code' running the calculation
! "destructors": ! stop code components in reverse order
call profiling_end()
call calc_mode_par_end()
call io_end()
call walltimer_end()
call messages_end()
call parser_end()
call global_end()
end programme
The actual calculation is started from the routine run(), which initialized the data structures representing the actual system and calculation mode, before starting the corresponding calculation:
main/run.F90
defines the module run_oct_m:
This module does not contain own data (apart from constants).
scf/ground_state.F90:
subroutine ground_state_run(system, from_scratch)
class(*), intent(inout) :: system
logical, intent(inout) :: from_scratch
PUSH_SUB(ground_state_run)
select type (system)
class is (multisystem_basic_t)
message(1) = "CalculationMode = gs not implemented for multi-system calculations"
call messages_fatal(1, namespace=system%namespace)
type is (electrons_t)
call ground_state_run_legacy(system, from_scratch)
end select
POP_SUB(ground_state_run)
end subroutine ground_state_run
subroutine ground_state_run_legacy(electrons, from_scratch)
class(electrons_t), intent(inout) :: electrons
logical, intent(inout) :: from_scratch
PUSH_SUB(ground_state_run_legacy)
call electrons_ground_state_run(electrons%namespace, electrons%mc, electrons%gr, electrons%ions, electrons%ext_partners, &
electrons%st, electrons%ks, electrons%hm, electrons%outp, electrons%space, from_scratch)
POP_SUB(ground_state_run_legacy)
end subroutine ground_state_run_legacy
subroutine electrons_ground_state_run(namespace, mc, gr, ions, ext_partners, st, ks, hm, outp, space, fromScratch)
type(namespace_t), intent(in) :: namespace
type(multicomm_t), intent(in) :: mc
type(grid_t), intent(inout) :: gr
type(ions_t), intent(inout) :: ions
type(partner_list_t), intent(in) :: ext_partners
type(states_elec_t), intent(inout) :: st
type(v_ks_t), intent(inout) :: ks
type(hamiltonian_elec_t), intent(inout) :: hm
type(output_t), intent(in) :: outp
type(space_t), intent(in) :: space
logical, intent(inout) :: fromScratch
type(scf_t) :: scfv
type(restart_t) :: restart_load, restart_dump
integer :: ierr
type(rdm_t) :: rdm
logical :: restart_init_dump
PUSH_SUB(ground_state_run_legacy)
call messages_write('Info: Allocating ground state wave-functions')
call messages_info(namespace=namespace)
if (st%parallel_in_states) then
call messages_experimental('State parallelization for ground state calculations', namespace=namespace)
end if
if (hm%pcm%run_pcm) then
if (hm%pcm%epsilon_infty /= hm%pcm%epsilon_0 .and. hm%pcm%tdlevel /= PCM_TD_EQ) then
message(1) = 'Non-equilbrium PCM is not active in a time-independent run.'
message(2) = 'You set epsilon_infty /= epsilon_0, but epsilon_infty is not relevant for CalculationMode = gs.'
message(3) = 'By definition, the ground state is in equilibrium with the solvent.'
message(4) = 'Therefore, the only relevant dielectric constant is the static one.'
message(5) = 'Nevertheless, the dynamical PCM response matrix is evaluated for benchamarking purposes.'
call messages_warning(5, namespace=namespace)
end if
end if
call states_elec_allocate_wfns(st, gr, packed=.true.)
! sometimes a deadlock can occur here (if some nodes can allocate and other cannot)
if (st%dom_st_kpt_mpi_grp%comm > 0) call st%dom_st_kpt_mpi_grp%barrier()
call messages_write('Info: Ground-state allocation done.')
call messages_info(namespace=namespace)
if (.not. fromScratch) then
! load wavefunctions
! in RDMFT we need the full ground state
call restart_init(restart_load, namespace, RESTART_GS, RESTART_TYPE_LOAD, mc, ierr, mesh=gr, &
exact = (ks%theory_level == RDMFT))
if (ierr == 0) then
call states_elec_load(restart_load, namespace, space, st, gr, hm%kpoints, ierr)
end if
if (ierr /= 0) then
call messages_write("Unable to read wavefunctions.")
call messages_new_line()
call messages_write("Starting from scratch!")
call messages_warning(namespace=namespace)
fromScratch = .true.
end if
end if
call write_canonicalized_xyz_file("exec", "initial_coordinates", space, ions%latt, ions%pos, ions%atom, &
gr%box, namespace)
if (ks%theory_level /= RDMFT) then
call scf_init(scfv, namespace, gr, ions, st, mc, hm, ks, space)
! only initialize dumping restart files for more than one iteration
restart_init_dump = scfv%max_iter > 0
else
restart_init_dump = .true.
end if
if (fromScratch .and. ks%theory_level /= RDMFT) then
call lcao_run(namespace, space, gr, ions, ext_partners, st, ks, hm, lmm_r = scfv%lmm_r)
else
! setup Hamiltonian
call messages_write('Info: Setting up Hamiltonian.')
call messages_info(namespace=namespace)
call v_ks_h_setup(namespace, space, gr, ions, ext_partners, st, ks, hm, &
calc_eigenval = .false., calc_current = .false.)
end if
if (restart_init_dump) then
call restart_init(restart_dump, namespace, RESTART_GS, RESTART_TYPE_DUMP, mc, ierr, mesh=gr)
end if
! run self-consistency
call scf_state_info(namespace, st)
if (st%d%pack_states .and. hm%apply_packed()) then
call st%pack()
end if
! self-consistency for occupation numbers and natural orbitals in RDMFT
if (ks%theory_level == RDMFT) then
call rdmft_init(rdm, namespace, gr, st, mc, space, fromScratch)
call scf_rdmft(rdm, namespace, space, gr, ions, ext_partners, st, ks, hm, outp, restart_dump)
call rdmft_end(rdm)
else
if (.not. fromScratch) then
if (restart_init_dump) then
call scf_run(scfv, namespace, space, mc, gr, ions, ext_partners, st, ks, hm, outp, &
restart_load=restart_load, restart_dump=restart_dump)
else
call scf_run(scfv, namespace, space, mc, gr, ions, ext_partners, st, ks, hm, outp, restart_load=restart_load)
end if
call restart_end(restart_load)
else
if (restart_init_dump) then
call scf_run(scfv, namespace, space, mc, gr, ions, ext_partners, st, ks, hm, outp, restart_dump=restart_dump)
else
call scf_run(scfv, namespace, space, mc, gr, ions, ext_partners, st, ks, hm, outp)
end if
end if
call scf_end(scfv)
end if
if (restart_init_dump) then
call restart_end(restart_dump)
end if
if (st%d%pack_states .and. hm%apply_packed()) then
call st%unpack()
end if
! clean up
call states_elec_deallocate_wfns(st)
POP_SUB(ground_state_run_legacy)
end subroutine electrons_ground_state_run