NAME

       gmap, gpart - compute static mappings and partitions sequentially

SYNOPSIS

       gmap [options] [gfile] [tfile] [mfile] [lfile]

       gpart [options] [nparts] [gfile] [mfile] [lfile]

DESCRIPTION

       The gmap program computes, in a sequential way, a static mapping of a source graph onto a target graph.

       The gpart program is a shortcut of gmap for computing unweighted partitions of a source graph.

       Source  graph  file  gfile  can  only be a centralized graph file. For gmap, the target architecture file
       tfile describes either algorithmically-coded topologies such as meshes and hypercubes, or  decomposition-
       defined architectures created by means of the amk_grf(1) program. The resulting mapping is stored in file
       mfile. Eventual logging information (such as the one produced by option -v) is sent to file  lfile.  When
       file  names  are not specified, data is read from standard input and written to standard output. Standard
       streams can also be explicitely represented by a dash '-'.

       When the proper libraries have been included  at  compile  time,  gmap  and  gpart  can  directly  handle
       compressed  graphs,  both  as  input  and  output. A stream is treated as compressed whenever its name is
       postfixed with a compressed file extension, such as in 'brol.grf.bz2' or '-.gz'. The compression  formats
       which  can  be  supported  are  the  bzip2  format ('.bz2'), the gzip format ('.gz'), and the lzma format
       ('.lzma', on input only).

OPTIONS

       -copt  Choose default mapping strategy according to one or several options among:

              b      enforce load balance as much as possible.

              q      privilege quality over speed (default).

              s      privilege speed over quality.

              t      enforce safety.

       -h     Display some help.

       -mstrat
              Use sequential mapping strategy strat (see Scotch user's manual for more information).

       -V     Display program version and copyright.

       -vverb Set verbose mode to verb. It is a set of one of more characters which can be:

              m      mapping information.

              s      strategy information.

              t      timing information.

TARGET ARCHITECTURES

       Target architectures represent graphs onto which source graphs are  mapped.  In  order  to  speed-up  the
       obtainment  of  target  architecture  topological  properties  during  the  computation of mappings, some
       classical topologies are algorithmically coded into the mapper itself. These topologies are  consequently
       simply defined by their code name, followed by their dimensional parameters:

       cmplt dim
              unweighted complete graph of size dim.

       cmpltw dim w0 w1 ... wdim-1
              weighted complete graph of size size and of respective loads w0, w1, ..., wdim-1.

       hcub dim
              hypercube of dimension dim.

       leaf hgt n0 w0 ... nhgt-1 whgt-1
              tree-leaf  graph  of  height  hgt with (n0 times n1 times ... nhgt-1) vertices, with inter-cluster
              link weights of w0, w1, ... whgt-1.

       mesh2D dimX dimY
              2D mesh of dimX times dimY nodes.

       mesh3D dimX dimY dimZ
              23 mesh of dimX times dimY times dimZ nodes.

       torus2D dimX dimY
              2D torus of dimX times dimY nodes.

       torus3D dimX dimY dimZ
              3D torus of dimX times dimY times dimZ nodes.

       Other target topologies can be created from their  source  graph  description  by  using  the  amk_grf(1)
       command. In this case, the target description will begin with the code name deco.

MAPPINGS

       Mappings  are represented by as many lines as there are vertices in the source graph. Each of these lines
       is made of two figures: the number of the vertex (or its label if source graph vertices are labeled)  and
       the  index  of the target vertex to which it has been assigned. Target vertex indices range from 0 to the
       number of vertices in the target architecture (that is, the number of parts) minus one.

       This block of lines is always preceded by the number of such lines. In most cases,  since  full  mappings
       are requested, the number of lines is equal to the number of vertices in the source graph.

EXAMPLES

       Run gpart to compute a partition into 7 parts of graph 'brol.grf' and save the resulting ordering to file
       'brol.map'.

           $ gpart 7 brol.grf brol.map

       Run gmap to compute a partition, into 3 parts of respective weights 1, 2 and 4, of graph  'brol.grf'  and
       save the resulting mapping to file 'brol.map'. The dash '-' standard file name is used so that the target
       architecture description is read from the standard input, through the pipe, as  provided  by  the  'echo'
       shell command.

           $ echo "cmpltw 3 1 2 4" | gmap brol.grf - brol.map

SEE ALSO

       amk_grf(1), acpl(1), gmtst(1), dgmap(1).

       Scotch user's manual.

AUTHOR

       Francois Pellegrini <francois.pellegrini@labri.fr>

                                                 August 03, 2010                                         gmap(1)