!!$ !!$ !!$ MD2P4 !!$ Multilevel Domain Decomposition Parallel Preconditioner Package for PSBLAS !!$ for !!$ Parallel Sparse BLAS v2.0 !!$ (C) Copyright 2006 Salvatore Filippone University of Rome Tor Vergata !!$ Alfredo Buttari University of Rome Tor Vergata !!$ Daniela di Serafino Second University of Naples !!$ Pasqua D'Ambra ICAR-CNR !!$ !!$ 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 MD2P4 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 MD2P4 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. !!$ !!$ subroutine mld_daggrmap_bld(aggr_type,a,desc_a,nlaggr,ilaggr,info) use psb_base_mod use psb_prec_mod, mld_protect_name => mld_daggrmap_bld implicit none integer, intent(in) :: aggr_type type(psb_dspmat_type), intent(in) :: a type(psb_desc_type), intent(in) :: desc_a integer, allocatable :: ilaggr(:),nlaggr(:) integer, intent(out) :: info ! Locals integer, allocatable :: ils(:), neigh(:) integer :: icnt,nlp,k,n,ia,isz,nr, naggr,i,j,m logical :: recovery logical, parameter :: debug=.false. integer ::ictxt,np,me,err_act integer :: nrow, ncol, n_ne integer, parameter :: one=1, two=2 character(len=20) :: name, ch_err if(psb_get_errstatus().ne.0) return info=0 name = 'mld_daggrmap_bld' call psb_erractionsave(err_act) ! ! Note. At the time being we are ignoring aggr_type ! so that we only have local decoupled aggregation. This might ! change in the future. ! ictxt=psb_cd_get_context(desc_a) call psb_info(ictxt,me,np) nrow = psb_cd_get_local_rows(desc_a) ncol = psb_cd_get_local_cols(desc_a) nr = a%m allocate(ilaggr(nr),neigh(nr),stat=info) if(info.ne.0) then info=4025 call psb_errpush(info,name,i_err=(/2*nr,0,0,0,0/),& & a_err='integer') goto 9999 end if do i=1, nr ilaggr(i) = -(nr+1) end do ! Note: -(nr+1) Untouched as yet ! -i 1<=i<=nr Adjacent to aggregate i ! i 1<=i<=nr Belonging to aggregate i ! ! Phase one: group nodes together. ! Very simple minded strategy. ! naggr = 0 nlp = 0 do icnt = 0 do i=1, nr if (ilaggr(i) == -(nr+1)) then ! ! 1. Untouched nodes are marked >0 together ! with their neighbours ! icnt = icnt + 1 naggr = naggr + 1 ilaggr(i) = naggr call psb_neigh(a,i,neigh,n_ne,info,lev=one) if (info/=0) then info=4010 ch_err='psb_neigh' call psb_errpush(info,name,a_err=ch_err) goto 9999 end if do k=1, n_ne j = neigh(k) if ((1<=j).and.(j<=nr)) then ilaggr(j) = naggr !!$ if (ilaggr(j) < 0) ilaggr(j) = naggr !!$ if (ilaggr(j) == -(nr+1)) ilaggr(j) = naggr endif enddo ! ! 2. Untouched neighbours of these nodes are marked <0. ! call psb_neigh(a,i,neigh,n_ne,info,lev=two) if (info/=0) then info=4010 ch_err='psb_neigh' call psb_errpush(info,name,a_err=ch_err) goto 9999 end if do n = 1, n_ne m = neigh(n) if ((1<=m).and.(m<=nr)) then if (ilaggr(m) == -(nr+1)) ilaggr(m) = -naggr endif enddo endif enddo nlp = nlp + 1 if (icnt == 0) exit enddo if (debug) then write(0,*) 'Check 1:',count(ilaggr == -(nr+1)),(a%ia1(i),i=a%ia2(1),a%ia2(2)-1) end if ! ! Phase two: sweep over leftovers. ! allocate(ils(naggr+10),stat=info) if(info.ne.0) then info=4025 call psb_errpush(info,name,i_err=(/naggr+10,0,0,0,0/),& & a_err='integer') goto 9999 end if do i=1, size(ils) ils(i) = 0 end do do i=1, nr n = ilaggr(i) if (n>0) then if (n>naggr) then write(0,*) 'loc_Aggregate: n > naggr 1 ? ',n,naggr else ils(n) = ils(n) + 1 end if end if end do if (debug) then write(0,*) 'Phase 1: number of aggregates ',naggr write(0,*) 'Phase 1: nodes aggregated ',sum(ils) end if recovery=.false. do i=1, nr if (ilaggr(i) < 0) then ! ! Now some silly rule to break ties: ! Group with smallest adjacent aggregate. ! isz = nr+1 ia = -1 call psb_neigh(a,i,neigh,n_ne,info,lev=one) if (info/=0) then info=4010 ch_err='psb_neigh' call psb_errpush(info,name,a_err=ch_err) goto 9999 end if do j=1, n_ne k = neigh(j) if ((1<=k).and.(k<=nr)) then n = ilaggr(k) if (n>0) then if (n>naggr) then write(0,*) 'loc_Aggregate: n > naggr 2? ',n,naggr end if if (ils(n) < isz) then ia = n isz = ils(n) endif endif endif enddo if (ia == -1) then if (ilaggr(i) > -(nr+1)) then ilaggr(i) = abs(ilaggr(i)) if (ilaggr(I)>naggr) then write(0,*) 'loc_Aggregate: n > naggr 3? ',ilaggr(i),naggr end if ils(ilaggr(i)) = ils(ilaggr(i)) + 1 ! ! This might happen if the pattern is non symmetric. ! Need a better handling. ! recovery = .true. else write(0,*) 'Unrecoverable error !!',ilaggr(i), nr endif else ilaggr(i) = ia if (ia>naggr) then write(0,*) 'loc_Aggregate: n > naggr 4? ',ia,naggr end if ils(ia) = ils(ia) + 1 endif end if enddo if (recovery) then write(0,*) 'Had to recover from strange situation in loc_aggregate.' write(0,*) 'Perhaps an unsymmetric pattern?' endif if (debug) then write(0,*) 'Phase 2: number of aggregates ',naggr write(0,*) 'Phase 2: nodes aggregated ',sum(ils) do i=1, naggr write(*,*) 'Size of aggregate ',i,' :',count(ilaggr==i), ils(i) enddo write(*,*) maxval(ils(1:naggr)) write(*,*) 'Leftovers ',count(ilaggr<0), ' in ',nlp,' loops' end if !!$ write(0,*) 'desc_a loc_aggr 4 : ', desc_a%matrix_data(m_) if (count(ilaggr<0) >0) then write(0,*) 'Fatal error: some leftovers!!!' endif deallocate(ils,neigh,stat=info) if (info/=0) then info=4000 call psb_errpush(info,name) goto 9999 end if if (nrow /= size(ilaggr)) then write(0,*) 'SOmething wrong ilaggr ',nrow,size(ilaggr) endif call psb_realloc(ncol,ilaggr,info) if (info/=0) then info=4010 ch_err='psb_realloc' call psb_errpush(info,name,a_err=ch_err) goto 9999 end if allocate(nlaggr(np),stat=info) if (info/=0) then info=4025 call psb_errpush(info,name,i_err=(/np,0,0,0,0/),& & a_err='integer') goto 9999 end if nlaggr(:) = 0 nlaggr(me+1) = naggr call psb_sum(ictxt,nlaggr(1:np)) call psb_erractionrestore(err_act) return 9999 continue call psb_erractionrestore(err_act) if (err_act.eq.psb_act_abort_) then call psb_error() return end if return end subroutine mld_daggrmap_bld