SuperLU_DIST  4.0
superlu_dist on CPU and GPU clusters
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Functions
comm.c File Reference

Broadcast an array of dtype numbers. More...

#include "superlu_ddefs.h"

Functions

void bcast_tree (void *buf, int count, MPI_Datatype dtype, int root, int tag, gridinfo_t *grid, int scope, int *recvcnt)
 

Detailed Description

Broadcast an array of dtype numbers.

– Distributed SuperLU routine (version 1.0) –
Lawrence Berkeley National Lab, Univ. of California Berkeley.
September 1, 1999

Function Documentation

void bcast_tree ( void *  buf,
int  count,
MPI_Datatype  dtype,
int  root,
int  tag,
gridinfo_t grid,
int  scope,
int *  recvcnt 
)

Purpose

  Broadcast an array of dtype numbers. The communication pattern
  is a tree with number of branches equal to NBRANCHES.
  The process ranks are between 0 and Np-1.
  The following two pairs of graphs give different ways of viewing the same
  algorithm.  The first pair shows the trees as they should be visualized
  when examining the algorithm.  The second pair are isomorphic graphs of
  of the first, which show the actual pattern of data movement.
  Note that a tree broadcast with NBRANCHES = 2 is isomorphic with a
  hypercube broadcast (however, it does not require the nodes be a
  power of two to work).
   TREE BROADCAST, NBRANCHES = 2     *    TREE BROADCAST, NBRANCHES = 3
    root=2
i=4   &______________                *
      |              \               *       root=2
i=2   &______         &______        * i=3     &______________________
      |      \        |      \       *         |          \           \
i=1   &__     &__     &__     &__    * i=1     &______     &______     &__
      |  \    |  \    |  \    |  \   *         |  \   \    |  \   \    |  \
      2   3   4   5   6   7   0   1  *         2   3   4   5   6   7   0   1
     ISOMORPHIC GRAPHS OF ABOVE, SHOWN IN MORE FAMILIAR TERMS:

           2                                           2
  _________|_________                       ___________|____________
 /         |         \                     /           |      |     \
6          4          3                   5            0      3      4

/ \ | / \ | 0 7 5 6 7 1 | 1

Arguments

scope