! ! ! AMG4PSBLAS version 1.0 ! Algebraic Multigrid Package ! based on PSBLAS (Parallel Sparse BLAS version 3.5) ! ! (C) Copyright 2020 ! ! Salvatore Filippone ! Pasqua D'Ambra ! Fabio Durastante ! ! Redistribution and use in source and binary forms, with or without ! modification, are permitted provided that the following conditions ! are met: ! 1. Redistributions of source code must retain the above copyright ! notice, this list of conditions and the following disclaimer. ! 2. Redistributions in binary form must reproduce the above copyright ! notice, this list of conditions, and the following disclaimer in the ! documentation and/or other materials provided with the distribution. ! 3. The name of the AMG4PSBLAS group or the names of its contributors may ! not be used to endorse or promote products derived from this ! software without specific written permission. ! ! THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ! ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED ! TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR ! PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AMG4PSBLAS GROUP OR ITS CONTRIBUTORS ! BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR ! CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF ! SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS ! INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN ! CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ! ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE ! POSSIBILITY OF SUCH DAMAGE. ! ! ! File: amg_d_hierarchy_bld.f90 ! ! Subroutine: amg_d_hierarchy_bld ! Version: real ! ! This routine builds the preconditioner according to the requirements made by ! the user trough the subroutines amg_precinit and amg_precset. ! ! A multilevel preconditioner is regarded as an array of 'one-level' data structures, ! each containing the part of the preconditioner associated to a certain level, ! (for more details see the description of amg_Tonelev_type in amg_prec_type.f90). ! The levels are numbered in increasing order starting from the finest one, i.e. ! level 1 is the finest level. No transfer operators are associated to level 1. ! ! ! Arguments: ! a - type(psb_dspmat_type). ! The sparse matrix structure containing the local part of the ! matrix to be preconditioned. ! desc_a - type(psb_desc_type), input. ! The communication descriptor of a. ! p - type(amg_dprec_type), input/output. ! The preconditioner data structure; upon exit it contains ! the multilevel hierarchy of prolongators, restrictors ! and coarse matrices. ! info - integer, output. ! Error code. ! subroutine amg_d_hierarchy_bld(a,desc_a,prec,info) use psb_base_mod use amg_d_inner_mod use amg_d_prec_mod, amg_protect_name => amg_d_hierarchy_bld Implicit None ! Arguments type(psb_dspmat_type),intent(in), target :: a type(psb_desc_type), intent(inout), target :: desc_a class(amg_dprec_type),intent(inout),target :: prec integer(psb_ipk_), intent(out) :: info ! Local Variables integer(psb_ipk_) :: ictxt, me,np integer(psb_ipk_) :: err,i,k, err_act, iszv, newsz,& & nplevs, mxplevs integer(psb_lpk_) :: iaggsize, casize real(psb_dpk_) :: mnaggratio, sizeratio, athresh, aomega class(amg_d_base_smoother_type), allocatable :: coarse_sm, med_sm, & & med_sm2, coarse_sm2 class(amg_d_base_aggregator_type), allocatable :: tmp_aggr type(amg_dml_parms) :: medparms, coarseparms integer(psb_lpk_), allocatable :: ilaggr(:), nlaggr(:) type(psb_ldspmat_type) :: op_prol type(amg_d_onelev_type), allocatable :: tprecv(:) integer(psb_ipk_) :: debug_level, debug_unit character(len=20) :: name, ch_err integer(psb_ipk_), save :: idx_bldtp=-1, idx_matasb=-1 logical, parameter :: do_timings=.false. info=psb_success_ err=0 call psb_erractionsave(err_act) if (psb_errstatus_fatal()) then info = psb_err_internal_error_; goto 9999 end if debug_unit = psb_get_debug_unit() debug_level = psb_get_debug_level() name = 'amg_d_hierarchy_bld' info = psb_success_ ictxt = desc_a%get_context() call psb_info(ictxt, me, np) prec%ictxt = ictxt if (debug_level >= psb_debug_outer_) & & write(debug_unit,*) me,' ',trim(name),& & 'Entering ' if ((do_timings).and.(idx_bldtp==-1)) & & idx_bldtp = psb_get_timer_idx("BLD_HIER: bld_tprol") if ((do_timings).and.(idx_matasb==-1)) & & idx_matasb = psb_get_timer_idx("BLD_HIER: mmat_asb") ! if (.not.allocated(prec%precv)) then !! Error: should have called amg_dprecinit info=3111 call psb_errpush(info,name) goto 9999 end if ! ! Check to ensure all procs have the same ! newsz = -1 mxplevs = prec%ag_data%max_levs mnaggratio = prec%ag_data%min_cr_ratio casize = prec%ag_data%min_coarse_size iszv = size(prec%precv) call psb_bcast(ictxt,iszv) call psb_bcast(ictxt,casize) call psb_bcast(ictxt,mxplevs) call psb_bcast(ictxt,mnaggratio) if (casize /= prec%ag_data%min_coarse_size) then info=psb_err_internal_error_ call psb_errpush(info,name,a_err='Inconsistent min_coarse_size') goto 9999 end if if (mxplevs /= prec%ag_data%max_levs) then info=psb_err_internal_error_ call psb_errpush(info,name,a_err='Inconsistent max_levs') goto 9999 end if if (mnaggratio /= prec%ag_data%min_cr_ratio) then info=psb_err_internal_error_ call psb_errpush(info,name,a_err='Inconsistent min_cr_ratio') goto 9999 end if if (iszv /= size(prec%precv)) then info=psb_err_internal_error_ call psb_errpush(info,name,a_err='Inconsistent size of precv') goto 9999 end if if (iszv < 1) then ! ! This is wrong, cannot be size <1 ! info=psb_err_from_subroutine_ ch_err='size bpv' call psb_errpush(info,name,a_err=ch_err) goto 9999 endif if (iszv == 1) then ! ! This is OK, since it may be called by the user even if there ! is only one level ! prec%precv(1)%base_a => a prec%precv(1)%base_desc => desc_a call psb_erractionrestore(err_act) return endif ! ! The strategy: ! 1. The maximum number of levels should be already encoded in the ! size of the array; ! 2. If the user did not specify anything, then a default coarse size ! is generated, and the number of levels is set to the maximum; ! 3. If the size of the array is different from target number of levels, ! reallocate; ! 4. Build the matrix hierarchy, stopping early if either the target ! coarse size is hit, or the gain falls below the min_cr_ratio ! threshold. ! if (casize < 0) then ! ! Default to the cubic root of the size at base level. ! casize = desc_a%get_global_rows() casize = int((done*casize)**(done/(done*3)),psb_lpk_) casize = max(casize,lone) casize = casize*40_psb_lpk_ call psb_bcast(ictxt,casize) if (casize > huge(prec%ag_data%min_coarse_size)) then ! ! computed coarse size does not fit in IPK_. ! This is very unlikely, but make sure to put a positive number ! prec%ag_data%min_coarse_size = huge(prec%ag_data%min_coarse_size) else prec%ag_data%min_coarse_size = casize end if end if nplevs = max(itwo,mxplevs) ! ! The coarse parameters will be needed later ! coarseparms = prec%precv(iszv)%parms call save_smoothers(prec%precv(iszv),coarse_sm,coarse_sm2,info) if (info /= psb_success_) then call psb_errpush(psb_err_internal_error_,name,a_err='Base level precbuild.') goto 9999 end if ! ! First set desired number of levels ! if (iszv /= nplevs) then allocate(tprecv(nplevs),stat=info) ! First all existing levels do i=1, min(iszv,nplevs) - 1 if (info == 0) tprecv(i)%parms = prec%precv(i)%parms if (info == 0) call restore_smoothers(tprecv(i),& & prec%precv(i)%sm,prec%precv(i)%sm2a,info) if (info == 0) call move_alloc(prec%precv(i)%aggr,tprecv(i)%aggr) end do if (iszv < nplevs) then ! Further intermediates, if needed allocate(tmp_aggr,source=tprecv(iszv-1)%aggr,stat=info) medparms = prec%precv(iszv-1)%parms call save_smoothers(prec%precv(iszv-1),med_sm,med_sm2,info) do i=iszv, nplevs - 1 if (info == 0) tprecv(i)%parms = medparms if (info == 0) call restore_smoothers(tprecv(i),med_sm,med_sm2,info) if ((info == 0).and..not.allocated(tprecv(i)%aggr))& & allocate(tprecv(i)%aggr,source=tmp_aggr,stat=info) end do deallocate(tmp_aggr,stat=info) end if ! Then coarse if (info == 0) tprecv(nplevs)%parms = coarseparms if (info == 0) call restore_smoothers(tprecv(nplevs),coarse_sm,coarse_sm2,info) if (info == 0) then if (nplevs <= iszv) then allocate(tprecv(nplevs)%aggr,source=prec%precv(nplevs)%aggr,stat=info) else allocate(tmp_aggr,source=tprecv(nplevs-1)%aggr,stat=info) call move_alloc(tmp_aggr,tprecv(nplevs)%aggr) end if end if if (info /= psb_success_) then call psb_errpush(psb_err_from_subroutine_,name,& & a_err='prec reallocation') goto 9999 endif do i=1,iszv call prec%precv(i)%free(info) end do call move_alloc(tprecv,prec%precv) iszv = size(prec%precv) end if ! ! Finest level first; create a GEN_BLOCK ! copy of the descriptor. ! prec%precv(1)%base_a => a call psb_cd_renum_block(desc_a,prec%precv(1)%desc_ac,info) prec%precv(1)%base_desc => prec%precv(1)%desc_ac newsz = 0 array_build_loop: do i=2, iszv ! ! Check on the iprcparm contents: they should be the same ! on all processes. ! call psb_bcast(ictxt,prec%precv(i)%parms) ! ! Sanity checks on the parameters ! if (i= psb_debug_outer_) & & write(debug_unit,*) me,' ',trim(name),& & 'Calling mlprcbld at level ',i ! ! Build the mapping between levels i-1 and i and the matrix ! at level i ! if (do_timings) call psb_tic(idx_bldtp) if (info == psb_success_)& & call prec%precv(i)%bld_tprol(prec%precv(i-1)%base_a,& & prec%precv(i-1)%base_desc,& & ilaggr,nlaggr,op_prol,prec%ag_data,info) if (do_timings) call psb_toc(idx_bldtp) if (info /= psb_success_) then call psb_errpush(psb_err_internal_error_,name,& & a_err='Map build') goto 9999 endif if (debug_level >= psb_debug_outer_) & & write(debug_unit,*) me,' ',trim(name),& & 'Return from ',i,' call to bld_tprol', info ! ! Save op_prol just in case ! call op_prol%clone(prec%precv(i)%tprol,info) ! ! Check for early termination of aggregation loop. ! iaggsize = sum(nlaggr) sizeratio = iaggsize if (i==2) then sizeratio = desc_a%get_global_rows()/sizeratio else sizeratio = sum(prec%precv(i-1)%map%naggr)/sizeratio end if prec%precv(i)%szratio = sizeratio if (iaggsize <= casize) newsz = i if (i == iszv) newsz = i if (i>2) then if (sizeratio < mnaggratio) then if (sizeratio > 1) then newsz = i else ! ! We are not gaining ! newsz = i-1 end if end if if (all(nlaggr == prec%precv(i-1)%map%naggr)) then newsz=i-1 if (me == 0) then write(debug_unit,*) trim(name),& &': Warning: aggregates from level ',& & newsz write(debug_unit,*) trim(name),& &': to level ',& & iszv,' coincide.' write(debug_unit,*) trim(name),& &': Number of levels actually used :',newsz write(debug_unit,*) end if end if end if call psb_bcast(ictxt,newsz) if (newsz > 0) then ! ! This is awkward, we are saving the aggregation parms, for the sake ! of distr/repl matrix at coarse level. Should be rethought. ! athresh = prec%precv(newsz)%parms%aggr_thresh aomega = prec%precv(newsz)%parms%aggr_omega_val if (info == 0) prec%precv(newsz)%parms = coarseparms prec%precv(newsz)%parms%aggr_thresh = athresh prec%precv(newsz)%parms%aggr_omega_val = aomega if (info == 0) call restore_smoothers(prec%precv(newsz),& & coarse_sm,coarse_sm2,info) if (newsz < i) then ! ! We are going back and revisit a previous leve; ! recover the aggregation. ! ilaggr = prec%precv(newsz)%map%iaggr nlaggr = prec%precv(newsz)%map%naggr call prec%precv(newsz)%tprol%clone(op_prol,info) end if if (do_timings) call psb_tic(idx_matasb) if (info == psb_success_) call prec%precv(newsz)%mat_asb( & & prec%precv(newsz-1)%base_a,prec%precv(newsz-1)%base_desc,& & ilaggr,nlaggr,op_prol,info) if (do_timings) call psb_toc(idx_matasb) if (info /= 0) then call psb_errpush(psb_err_internal_error_,name,& & a_err='Mat asb') goto 9999 endif exit array_build_loop else if (do_timings) call psb_tic(idx_matasb) if (info == psb_success_) call prec%precv(i)%mat_asb(& & prec%precv(i-1)%base_a,prec%precv(i-1)%base_desc,& & ilaggr,nlaggr,op_prol,info) if (do_timings) call psb_toc(idx_matasb) end if if (info /= psb_success_) then call psb_errpush(psb_err_internal_error_,name,& & a_err='Map build') goto 9999 endif if (i 0) then ! ! We exited early from the build loop, need to fix ! the size. ! allocate(tprecv(newsz),stat=info) if (info /= psb_success_) then call psb_errpush(psb_err_from_subroutine_,name,& & a_err='prec reallocation') goto 9999 endif do i=1,newsz call prec%precv(i)%move_alloc(tprecv(i),info) end do do i=newsz+1, iszv call prec%precv(i)%free(info) end do call move_alloc(tprecv,prec%precv) ! Ignore errors from transfer info = psb_success_ ! ! Restart iszv = newsz ! Fix the pointers, but the level 1 should ! be treated differently if (.not.associated(prec%precv(1)%base_desc,desc_a)) then prec%precv(1)%base_desc => prec%precv(1)%desc_ac end if do i=2, iszv prec%precv(i)%base_a => prec%precv(i)%ac prec%precv(i)%base_desc => prec%precv(i)%desc_ac prec%precv(i)%map%p_desc_U => prec%precv(i-1)%base_desc prec%precv(i)%map%p_desc_V => prec%precv(i)%base_desc end do end if if (info /= psb_success_) then call psb_errpush(psb_err_internal_error_,name,& & a_err='Internal hierarchy build' ) goto 9999 endif iszv = size(prec%precv) call prec%cmp_complexity() call prec%cmp_avg_cr() if (debug_level >= psb_debug_outer_) & & write(debug_unit,*) me,' ',trim(name),& & 'Exiting with',iszv,' levels' call psb_erractionrestore(err_act) return 9999 call psb_error_handler(err_act) return contains subroutine save_smoothers(level,save1, save2,info) type(amg_d_onelev_type), intent(inout) :: level class(amg_d_base_smoother_type), allocatable , intent(inout) :: save1, save2 integer(psb_ipk_), intent(out) :: info info = 0 if (allocated(save1)) then call save1%free(info) if (info == 0) deallocate(save1,stat=info) if (info /= 0) return end if if (allocated(save2)) then call save2%free(info) if (info == 0) deallocate(save2,stat=info) if (info /= 0) return end if allocate(save1, mold=level%sm,stat=info) if (info == 0) call level%sm%clone_settings(save1,info) if ((info == 0).and.allocated(level%sm2a)) then allocate(save2, mold=level%sm2a,stat=info) if (info == 0) call level%sm2a%clone_settings(save2,info) end if return end subroutine save_smoothers subroutine restore_smoothers(level,save1, save2,info) type(amg_d_onelev_type), intent(inout), target :: level class(amg_d_base_smoother_type), allocatable, intent(inout) :: save1, save2 integer(psb_ipk_), intent(out) :: info info = 0 if (allocated(level%sm)) then if (info == 0) call level%sm%free(info) if (info == 0) deallocate(level%sm,stat=info) end if if (allocated(save1)) then if (info == 0) allocate(level%sm,mold=save1,stat=info) if (info == 0) call save1%clone_settings(level%sm,info) end if if (info /= 0) return if (allocated(level%sm2a)) then if (info == 0) call level%sm2a%free(info) if (info == 0) deallocate(level%sm2a,stat=info) end if if (allocated(save2)) then if (info == 0) allocate(level%sm2a,mold=save2,stat=info) if (info == 0) call save2%clone_settings(level%sm2a,info) if (info == 0) level%sm2 => level%sm2a else if (allocated(level%sm)) level%sm2 => level%sm end if return end subroutine restore_smoothers end subroutine amg_d_hierarchy_bld