xref: /petsc/src/dm/partitioner/impls/chaco/partchaco.c (revision e0b7e82fd3cf27fce84cc3e37e8d70a5c36a2d4e)
1 #include <petsc/private/partitionerimpl.h> /*I "petscpartitioner.h" I*/
2 
3 PetscBool  ChacoPartitionerCite       = PETSC_FALSE;
4 const char ChacoPartitionerCitation[] = "@inproceedings{Chaco95,\n"
5                                         "  author    = {Bruce Hendrickson and Robert Leland},\n"
6                                         "  title     = {A multilevel algorithm for partitioning graphs},\n"
7                                         "  booktitle = {Supercomputing '95: Proceedings of the 1995 ACM/IEEE Conference on Supercomputing (CDROM)},"
8                                         "  isbn      = {0-89791-816-9},\n"
9                                         "  pages     = {28},\n"
10                                         "  doi       = {https://doi.acm.org/10.1145/224170.224228},\n"
11                                         "  publisher = {ACM Press},\n"
12                                         "  address   = {New York},\n"
13                                         "  year      = {1995}\n"
14                                         "}\n";
15 
16 typedef struct {
17   PetscInt dummy;
18 } PetscPartitioner_Chaco;
19 
20 static PetscErrorCode PetscPartitionerDestroy_Chaco(PetscPartitioner part)
21 {
22   PetscPartitioner_Chaco *p = (PetscPartitioner_Chaco *)part->data;
23 
24   PetscFunctionBegin;
25   PetscCall(PetscFree(p));
26   PetscFunctionReturn(PETSC_SUCCESS);
27 }
28 
29 static PetscErrorCode PetscPartitionerView_Chaco_ASCII(PetscPartitioner part, PetscViewer viewer)
30 {
31   PetscFunctionBegin;
32   PetscFunctionReturn(PETSC_SUCCESS);
33 }
34 
35 static PetscErrorCode PetscPartitionerView_Chaco(PetscPartitioner part, PetscViewer viewer)
36 {
37   PetscBool iascii;
38 
39   PetscFunctionBegin;
40   PetscValidHeaderSpecific(part, PETSCPARTITIONER_CLASSID, 1);
41   PetscValidHeaderSpecific(viewer, PETSC_VIEWER_CLASSID, 2);
42   PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
43   if (iascii) PetscCall(PetscPartitionerView_Chaco_ASCII(part, viewer));
44   PetscFunctionReturn(PETSC_SUCCESS);
45 }
46 
47 #if defined(PETSC_HAVE_CHACO)
48   #if defined(PETSC_HAVE_UNISTD_H)
49     #include <unistd.h>
50   #endif
51   #if defined(PETSC_HAVE_CHACO_INT_ASSIGNMENT)
52     #include <chaco.h>
53   #else
54 /* Older versions of Chaco do not have an include file */
55 PETSC_EXTERN int interface(int nvtxs, int *start, int *adjacency, int *vwgts, float *ewgts, float *x, float *y, float *z, char *outassignname, char *outfilename, short *assignment, int architecture, int ndims_tot, int mesh_dims[3], double *goal, int global_method, int local_method, int rqi_flag, int vmax, int ndims, double eigtol, long seed);
56   #endif
57 extern int FREE_GRAPH;
58 #endif
59 
60 static PetscErrorCode PetscPartitionerPartition_Chaco(PetscPartitioner part, PetscInt nparts, PetscInt numVertices, PetscInt start[], PetscInt adjacency[], PetscSection vertSection, PetscSection edgeSection, PetscSection targetSection, PetscSection partSection, IS *partition)
61 {
62 #if defined(PETSC_HAVE_CHACO)
63   enum {
64     DEFAULT_METHOD  = 1,
65     INERTIAL_METHOD = 3
66   };
67   MPI_Comm comm;
68   int      nvtxs = numVertices;            /* number of vertices in full graph */
69   int     *vwgts = NULL;                   /* weights for all vertices */
70   float   *ewgts = NULL;                   /* weights for all edges */
71   float   *x = NULL, *y = NULL, *z = NULL; /* coordinates for inertial method */
72   char    *outassignname = NULL;           /*  name of assignment output file */
73   char    *outfilename   = NULL;           /* output file name */
74   int      architecture  = 1;              /* 0 => hypercube, d => d-dimensional mesh */
75   int      ndims_tot     = 0;              /* total number of cube dimensions to divide */
76   int      mesh_dims[3];                   /* dimensions of mesh of processors */
77   double  *goal          = NULL;           /* desired set sizes for each set */
78   int      global_method = 1;              /* global partitioning algorithm */
79   int      local_method  = 1;              /* local partitioning algorithm */
80   int      rqi_flag      = 0;              /* should I use RQI/Symmlq eigensolver? */
81   int      vmax          = 200;            /* how many vertices to coarsen down to? */
82   int      ndims         = 1;              /* number of eigenvectors (2^d sets) */
83   double   eigtol        = 0.001;          /* tolerance on eigenvectors */
84   long     seed          = 123636512;      /* for random graph mutations */
85   #if defined(PETSC_HAVE_CHACO_INT_ASSIGNMENT)
86   int *assignment; /* Output partition */
87   #else
88   short int *assignment; /* Output partition */
89   #endif
90   int       fd_stdout, fd_pipe[2];
91   PetscInt *points;
92   int       i, v, p;
93   int       err;
94 
95   PetscFunctionBegin;
96   PetscCall(PetscObjectGetComm((PetscObject)part, &comm));
97   if (PetscDefined(USE_DEBUG)) {
98     int       ival, isum;
99     PetscBool distributed;
100 
101     ival = (numVertices > 0);
102     PetscCallMPI(MPI_Allreduce(&ival, &isum, 1, MPI_INT, MPI_SUM, comm));
103     distributed = (isum > 1) ? PETSC_TRUE : PETSC_FALSE;
104     PetscCheck(!distributed, comm, PETSC_ERR_SUP, "Chaco cannot partition a distributed graph");
105   }
106   if (!numVertices) { /* distributed case, return if not holding the graph */
107     PetscCall(ISCreateGeneral(comm, 0, NULL, PETSC_OWN_POINTER, partition));
108     PetscFunctionReturn(PETSC_SUCCESS);
109   }
110   FREE_GRAPH = 0; /* Do not let Chaco free my memory */
111   for (i = 0; i < start[numVertices]; ++i) ++adjacency[i];
112 
113   /* code would use manager.createCellCoordinates(nvtxs, &x, &y, &z); */
114   PetscCheck(global_method != INERTIAL_METHOD, PETSC_COMM_SELF, PETSC_ERR_SUP, "Inertial partitioning not yet supported");
115 
116   mesh_dims[0] = nparts;
117   mesh_dims[1] = 1;
118   mesh_dims[2] = 1;
119   PetscCall(PetscMalloc1(nvtxs, &assignment));
120   /* Chaco outputs to stdout. We redirect this to a buffer. */
121   /* TODO: check error codes for UNIX calls */
122   #if defined(PETSC_HAVE_UNISTD_H)
123   {
124     int piperet;
125     piperet = pipe(fd_pipe);
126     PetscCheck(!piperet, PETSC_COMM_SELF, PETSC_ERR_SYS, "Could not create pipe");
127     fd_stdout = dup(1);
128     close(1);
129     dup2(fd_pipe[1], 1);
130   }
131   #endif
132   if (part->usevwgt) PetscCall(PetscInfo(part, "PETSCPARTITIONERCHACO ignores vertex weights\n"));
133   if (part->useewgt) PetscCall(PetscInfo(part, "PETSCPARTITIONERCHACO ignores edge weights\n"));
134   err = interface(nvtxs, (int *)start, (int *)adjacency, vwgts, ewgts, x, y, z, outassignname, outfilename, assignment, architecture, ndims_tot, mesh_dims, goal, global_method, local_method, rqi_flag, vmax, ndims, eigtol, seed);
135   #if defined(PETSC_HAVE_UNISTD_H)
136   {
137     char msgLog[10000];
138     int  count;
139 
140     PetscCall(PetscFFlush(stdout));
141     count = read(fd_pipe[0], msgLog, (10000 - 1) * sizeof(char));
142     if (count < 0) count = 0;
143     msgLog[count] = 0;
144     close(1);
145     dup2(fd_stdout, 1);
146     close(fd_stdout);
147     close(fd_pipe[0]);
148     close(fd_pipe[1]);
149     PetscCheck(!err, PETSC_COMM_SELF, PETSC_ERR_LIB, "Error in Chaco library: %s", msgLog);
150   }
151   #else
152   PetscCheck(!err, PETSC_COMM_SELF, PETSC_ERR_LIB, "Error in Chaco library: %s", "error in stdout");
153   #endif
154   /* Convert to PetscSection+IS */
155   for (v = 0; v < nvtxs; ++v) PetscCall(PetscSectionAddDof(partSection, assignment[v], 1));
156   PetscCall(PetscMalloc1(nvtxs, &points));
157   for (p = 0, i = 0; p < nparts; ++p) {
158     for (v = 0; v < nvtxs; ++v) {
159       if (assignment[v] == p) points[i++] = v;
160     }
161   }
162   PetscCheck(i == nvtxs, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Number of points %" PetscInt_FMT " should be %" PetscInt_FMT, i, nvtxs);
163   PetscCall(ISCreateGeneral(comm, nvtxs, points, PETSC_OWN_POINTER, partition));
164   /* code would use manager.destroyCellCoordinates(nvtxs, &x, &y, &z); */
165   PetscCheck(global_method != INERTIAL_METHOD, PETSC_COMM_SELF, PETSC_ERR_SUP, "Inertial partitioning not yet supported");
166   PetscCall(PetscFree(assignment));
167   for (i = 0; i < start[numVertices]; ++i) --adjacency[i];
168   PetscFunctionReturn(PETSC_SUCCESS);
169 #else
170   SETERRQ(PetscObjectComm((PetscObject)part), PETSC_ERR_SUP, "Mesh partitioning needs external package support.\nPlease reconfigure with --download-chaco.");
171 #endif
172 }
173 
174 static PetscErrorCode PetscPartitionerInitialize_Chaco(PetscPartitioner part)
175 {
176   PetscFunctionBegin;
177   part->noGraph        = PETSC_FALSE;
178   part->ops->view      = PetscPartitionerView_Chaco;
179   part->ops->destroy   = PetscPartitionerDestroy_Chaco;
180   part->ops->partition = PetscPartitionerPartition_Chaco;
181   PetscFunctionReturn(PETSC_SUCCESS);
182 }
183 
184 /*MC
185   PETSCPARTITIONERCHACO = "chaco" - A PetscPartitioner object using the Chaco library
186 
187   Level: intermediate
188 
189 .seealso: `PetscPartitionerType`, `PetscPartitionerCreate()`, `PetscPartitionerSetType()`
190 M*/
191 
192 PETSC_EXTERN PetscErrorCode PetscPartitionerCreate_Chaco(PetscPartitioner part)
193 {
194   PetscPartitioner_Chaco *p;
195 
196   PetscFunctionBegin;
197   PetscValidHeaderSpecific(part, PETSCPARTITIONER_CLASSID, 1);
198   PetscCall(PetscNew(&p));
199   part->data = p;
200 
201   PetscCall(PetscPartitionerInitialize_Chaco(part));
202   PetscCall(PetscCitationsRegister(ChacoPartitionerCitation, &ChacoPartitionerCite));
203   PetscFunctionReturn(PETSC_SUCCESS);
204 }
205