1gmap(1) Scotch user's manual gmap(1)
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6 gmap, gpart - compute static mappings and partitions sequentially
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9 gmap [options] [gfile] [tfile] [mfile] [lfile]
10 gpart [options] [nparts] [gfile] [mfile] [lfile]
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14 The gmap program computes, in a sequential way, a static mapping of a
15 source graph onto a target graph.
16 The gpart program is a shortcut of gmap for computing unweighted parti‐
18 tions of a source graph.
19 Source graph file gfile can only be a centralized graph file. For gmap,
21 the target architecture file tfile describes either algorithmically-
22 coded topologies such as meshes and hypercubes, or decomposition-
23 defined architectures created by means of the amk_grf(1) program. The
24 resulting mapping is stored in file mfile. Eventual logging information
25 (such as the one produced by option -v) is sent to file lfile. When
26 file names are not specified, data is read from standard input and
27 written to standard output. Standard streams can also be explicitely
28 represented by a dash '-'.
29 When the proper libraries have been included at compile time, gmap and
31 gpart can directly handle compressed graphs, both as input and output.
32 A stream is treated as compressed whenever its name is postfixed with a
33 compressed file extension, such as in supported are the bzip2 format
34 ('.bz2'), the gzip format ('.gz'), and the lzma format ('.lzma', on
35 input only).
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38 -h Display some help.
39 -mstrat
41 Use sequential mapping strategy strat (see Scotch user's manual
42 for more information).
43 -V Display program version and copyright.
45 -vverb Set verbose mode to verb. It is a set of one of more characters
47 which can be:
48 m mapping information.
50 s strategy information.
52 t timing information.
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56 Target architectures represent graphs onto which source graphs are
57 mapped. In order to speed-up the obtainment of target architecture
58 topological properties during the computation of mappings, some classi‐
59 cal topologies are algorithmically coded into the mapper itself. These
60 topologies are consequently simply defined by their code name, followed
61 by their dimensional parameters:
62 cmplt dim
64 unweighted complete graph of size dim.
65 cmpltw dim w0 w1 ... wdim-1
67 weighted complete graph of size size and of respective loads w0,
68 w1, ..., wdim-1.
69 hcub dim
71 hypercube of dimension dim.
72 leaf hgt clu wgt
74 tree-leaf graph of height hgt with 2^hgt vertices, clu levels
75 before reaching the processing elements, and an inter-cluster
76 link weight of wgt.
77 mesh2D dimX dimY
79 2D mesh of dimX times dimY nodes.
80 mesh3D dimX dimY dimZ
82 23 mesh of dimX times dimY times dimZ nodes.
83 torus2D dimX dimY
85 2D torus of dimX times dimY nodes.
86 torus3D dimX dimY dimZ
88 3D torus of dimX times dimY times dimZ nodes.
89 Other target topologies can be created from their source graph descrip‐
91 tion by using the amk_grf(1) command. In this case, the target descrip‐
92 tion will begin with the code name deco.
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95 Mappings are represented by as many lines as there are vertices in the
96 source graph. Each of these lines is made of two figures: the number of
97 the vertex (or its label if source graph vertices are labeled) and the
98 index of the target vertex to which it has been assigned. Target vertex
99 indices range from 0 to the number of vertices in the target architec‐
100 ture (that is, the number of parts) minus one.
101 This block of lines is always preceded by the number of such lines. In
103 most cases, since full mappings are requested, the number of lines is
104 equal to the number of vertices in the source graph.
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107 Run gpart to compute a partition into 7 parts of graph brol.grf and
108 save the resulting ordering to file brol.map.
109 $ gpart 7 brol.grf brol.map
111 Run gmap to compute a partition, into 3 parts of respective weights 1,
113 2 and 4, of graph brol.grf and save the resulting mapping to file
114 brol.map. The dash '-' standard file name is used so that the target
115 architecture description is read from the standard input, through the
116 pipe, as provided by the 'echo' shell command.
117 $ echo "cmpltw 3 1 2 4" | gmap brol.grf - brol.map
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122 amk_grf(1), acpl(1), gmtst(1), dgmap(1).
123 Scotch user's manual.
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127 Francois Pellegrini <francois.pellegrini@labri.fr>
128 September 08, 2008 gmap(1)