fdurastante/psblas3
1
0
Fork 0
mirror of https://github.com/sfilippone/psblas3.git synced 2026-10-16 10:52:08 +00:00
Code Issues Packages Projects Releases Wiki Activity

Shuffled around internal docs.

Browse Source
This commit is contained in:
Salvatore Filippone
2007-10-05 12:35:41 +00:00
parent 624e32ed6d
commit 9f0119ee5a
2 changed files with 76 additions and 50 deletions
Download Patch File Download Diff File Expand all files Collapse all files
base/internals/psi_crea_index.f90
+3 -49
View File
@@ -34,7 +34,9 @@
!
! Subroutine: psb_crea_index
! Converts a list of data exchanges from build format to assembled format.
! See below for a description of the formats.
! See psi_desc_index for a description of the formats.
! Works by first finding a suitable ordering for the data exchanges,
! then doing the actual conversion.
!
! Arguments:
! desc_a - type(psb_desc_type) The descriptor; in this context only the index
@@ -48,54 +50,6 @@
! nsnd - integer Total send buffer size on the calling process
! nrcv - integer Total receive buffer size on the calling process
!
!
! The format of the index lists. Copied from base/modules/psb_desc_type
!
! 7. The data exchange is based on lists of local indices to be exchanged; all the
! lists have the same format, as follows:
! the list is composed of variable dimension blocks, one for each process to
! communicate with; each block contains indices of local elements to be
! exchanged. We do choose the order of communications: do not change
! the sequence of blocks unless you know what you're doing, or you'll
! risk a deadlock. NOTE: This is the format when the state is PSB_ASB_.
! See below for BLD. The end-of-list is marked with a -1.
!
! notation stored in explanation
! --------------- --------------------------- -----------------------------------
! process_id index_v(p+proc_id_) identifier of process with which
! data is exchanged.
! n_elements_recv index_v(p+n_elem_recv_) number of elements to receive.
! elements_recv index_v(p+elem_recv_+i) indexes of local elements to
! receive. these are stored in the
! array from location p+elem_recv_ to
! location p+elem_recv_+
! index_v(p+n_elem_recv_)-1.
! n_elements_send index_v(p+n_elem_send_) number of elements to send.
! elements_send index_v(p+elem_send_+i) indexes of local elements to
! send. these are stored in the
! array from location p+elem_send_ to
! location p+elem_send_+
! index_v(p+n_elem_send_)-1.
!
! This organization is valid for both halo and overlap indices; overlap entries
! need to be updated to ensure that a variable at a given global index
! (assigned to multiple processes) has the same value. The way to resolve the
! issue is to exchange the data and then sum (or average) the values. See
! psb_ovrl subroutine.
!
! 8. When the descriptor is in the BLD state the INDEX vectors contains only
! the indices to be received, organized as a sequence
! of entries of the form (proc,N,(lx1,lx2,...,lxn)) with owning process,
! number of indices (most often N=1), list of local indices.
! This is because we only know the list of halo indices to be received
! as we go about building the sparse matrix pattern, and we want the build
! phase to be loosely synchronized. Thus we record the indices we have to ask
! for, and at the time we call PSB_CDASB we match all the requests to figure
! out who should be sending what to whom.
! However this implies that we know who owns the indices; if we are in the
! LARGE case (as described above) this is actually only true for the OVERLAP list
! that is filled in at CDALL time, and not for the HALO; thus the HALO list
! is rebuilt during the CDASB process (in the psi_ldsc_pre_halo subroutine).
!
subroutine psi_crea_index(desc_a,index_in,index_out,glob_idx,nxch,nsnd,nrcv,info)
base/internals/psi_desc_index.F90
+73 -1
View File
@@ -28,6 +28,75 @@
!!$ POSSIBILITY OF SUCH DAMAGE.
!!$
!!$
!
!
! File: psi_desc_index.f90
!
! Subroutine: psi_desc_index
! Converts a list of data exchanges from build format to assembled format.
! See below for a description of the formats.
!
! Arguments:
! desc_a - type(psb_desc_type) The descriptor; in this context only the index
! mapping parts are used.
! index_in(:) - integer The index list, build format
! index_out(:) - integer, allocatable The index list, assembled format
! glob_idx - logical Whether the input indices are in local or global
! numbering; the global numbering is used when
! converting the overlap exchange lists.
! nxch - integer The number of data exchanges on the calling process
! nsnd - integer Total send buffer size on the calling process
! nrcv - integer Total receive buffer size on the calling process
!
! The format of the index lists. Copied from base/modules/psb_desc_type
!
! 7. The data exchange is based on lists of local indices to be exchanged; all the
! lists have the same format, as follows:
! the list is composed of variable dimension blocks, one for each process to
! communicate with; each block contains indices of local elements to be
! exchanged. We do choose the order of communications: do not change
! the sequence of blocks unless you know what you're doing, or you'll
! risk a deadlock. NOTE: This is the format when the state is PSB_ASB_.
! See below for BLD. The end-of-list is marked with a -1.
!
! notation stored in explanation
! --------------- --------------------------- -----------------------------------
! process_id index_v(p+proc_id_) identifier of process with which
! data is exchanged.
! n_elements_recv index_v(p+n_elem_recv_) number of elements to receive.
! elements_recv index_v(p+elem_recv_+i) indexes of local elements to
! receive. these are stored in the
! array from location p+elem_recv_ to
! location p+elem_recv_+
! index_v(p+n_elem_recv_)-1.
! n_elements_send index_v(p+n_elem_send_) number of elements to send.
! elements_send index_v(p+elem_send_+i) indexes of local elements to
! send. these are stored in the
! array from location p+elem_send_ to
! location p+elem_send_+
! index_v(p+n_elem_send_)-1.
!
! This organization is valid for both halo and overlap indices; overlap entries
! need to be updated to ensure that a variable at a given global index
! (assigned to multiple processes) has the same value. The way to resolve the
! issue is to exchange the data and then sum (or average) the values. See
! psb_ovrl subroutine.
!
! 8. When the descriptor is in the BLD state the INDEX vectors contains only
! the indices to be received, organized as a sequence
! of entries of the form (proc,N,(lx1,lx2,...,lxn)) with owning process,
! number of indices (most often N=1), list of local indices.
! This is because we only know the list of halo indices to be received
! as we go about building the sparse matrix pattern, and we want the build
! phase to be loosely synchronized. Thus we record the indices we have to ask
! for, and at the time we call PSB_CDASB we match all the requests to figure
! out who should be sending what to whom.
! However this implies that we know who owns the indices; if we are in the
! LARGE case (as described above) this is actually only true for the OVERLAP list
! that is filled in at CDALL time, and not for the HALO; thus the HALO list
! is rebuilt during the CDASB process (in the psi_ldsc_pre_halo subroutine).
!
!
subroutine psi_desc_index(desc,index_in,dep_list,&
& length_dl,nsnd,nrcv,desc_index,isglob_in,info)
use psb_descriptor_type
@@ -85,7 +154,7 @@ subroutine psi_desc_index(desc,index_in,dep_list,&
endif
!
! first, find out the total sizes to be exchanged.
! first, find out the sizes to be exchanged.
! note: things marked here as sndbuf/rcvbuf (for mpi) corresponds to things
! to be received/sent (in the final psblas descriptor).
! be careful of the inversion
@@ -166,6 +235,9 @@ subroutine psi_desc_index(desc,index_in,dep_list,&
goto 9999
end if
!
! Second build the lists of requests
!
i = 1
do
if (i > ihinsz) then