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DrTimothyAldenDavisDrTimothyAldenDavis
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exploit GrB v10.2.0: method 27, aliased assign kernel
1 parent 9e0616a commit e24e93c

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-60
lines changed

4 files changed

+120
-60
lines changed

‎experimental/algorithm/LAGr_EdgeBetweennessCentrality.c‎

Lines changed: 96 additions & 56 deletions
Original file line numberDiff line numberDiff line change
@@ -18,6 +18,7 @@
1818

1919
// TODO: ready for src, except need vanilla, and the method is a bit slow
2020
// because of the internal kernels it uses in SuiteSparse:GraphBLAS need work.
21+
// FIXED in v10.2 but may need more work in GraphBLAS.
2122

2223
// LAGr_EdgeBetweennessCentrality: Exact algorithm for computing
2324
// betweeness centrality.
@@ -27,7 +28,6 @@
2728
//------------------------------------------------------------------------------
2829

2930
#define useAssign
30-
// #define debug
3131

3232
#define LG_FREE_WORK \
3333
{ \
@@ -94,7 +94,9 @@ int LAGr_EdgeBetweennessCentrality
9494
GrB_Matrix *centrality, // centrality(i): betweeness centrality of i
9595
// input:
9696
LAGraph_Graph G, // input graph
97-
GrB_Vector sources, // source vertices to compute shortest paths (if NULL or empty, use all vertices)
97+
GrB_Vector sources, // source vertices to compute shortest paths
98+
// (if NULL or empty, use all vertices)
99+
98100
char *msg
99101
)
100102
{
@@ -217,11 +219,14 @@ int LAGr_EdgeBetweennessCentrality
217219
GRB_TRY (GrB_Vector_new (&bc_vertex_flow, GrB_FP64, n)) ;
218220

219221
// Initialize centrality matrix with zeros using A as structural mask
222+
// centrality<A,struct> = 0
220223
LG_TRY (GrB_Matrix_new(centrality, GrB_FP64, n, n)) ;
221-
GRB_TRY (GrB_assign (*centrality, A, NULL, 0.0, GrB_ALL, n, GrB_ALL, n, GrB_DESC_S)) ;
224+
GRB_TRY (GrB_assign (*centrality, A, NULL, 0.0, GrB_ALL, n, GrB_ALL, n,
225+
GrB_DESC_S)) ;
222226

223227
// Allocate memory for the array of S vectors
224-
LG_TRY (LAGraph_Calloc ((void **) &Search, n + 1, sizeof (GrB_Vector), msg)) ;
228+
LG_TRY (LAGraph_Calloc ((void **) &Search, n + 1, sizeof (GrB_Vector),
229+
msg)) ;
225230

226231
// =========================================================================
227232
// === Process source nodes ================================================
@@ -234,7 +239,8 @@ int LAGr_EdgeBetweennessCentrality
234239
GRB_TRY (GrB_Vector_new (&internal_sources, GrB_INT64, n)) ;
235240

236241
// internal_sources (0:n-1) = 0
237-
GRB_TRY (GrB_assign (internal_sources, NULL, NULL, 0, GrB_ALL, n, NULL)) ;
242+
GRB_TRY (GrB_assign (internal_sources, NULL, NULL, 0, GrB_ALL, n,
243+
NULL)) ;
238244

239245
// internal_sources (0:n-1) = 0:n-1
240246
GRB_TRY (GrB_apply (internal_sources, NULL, NULL, GrB_ROWINDEX_INT64,
@@ -266,7 +272,7 @@ int LAGr_EdgeBetweennessCentrality
266272
GRB_TRY (GrB_Vector_new(&J_vec, GrB_FP64, n)) ;
267273
GRB_TRY (GrB_Vector_new (&I_vec, GrB_FP64, n)) ;
268274
GRB_TRY (GrB_Matrix_new (&Fd1A, GrB_FP64, n, n)) ;
269-
GRB_TRY (GrB_Vector_new(&temp_update, GrB_FP64, n)) ; // Create a temporary vector
275+
GRB_TRY (GrB_Vector_new(&temp_update, GrB_FP64, n)) ; // Create temp vector
270276

271277
GRB_TRY (GrB_Matrix_new(&HalfUpdate, GrB_FP64, n, n)) ;
272278
GRB_TRY (GrB_Matrix_new(&HalfUpdateT, GrB_FP64, n, n)) ;
@@ -298,51 +304,54 @@ int LAGr_EdgeBetweennessCentrality
298304
GrB_DESC_T0)) ;
299305

300306
GRB_TRY (GrB_Vector_nvals (&frontier_size, frontier)) ;
301-
GRB_TRY (GrB_assign (frontier, frontier, NULL, 1.0, GrB_ALL, n, GrB_DESC_S)) ;
307+
GRB_TRY (GrB_assign (frontier, frontier, NULL, 1.0, GrB_ALL, n,
308+
GrB_DESC_S)) ;
302309

303310
while (frontier_size != 0)
304311
{
305312
depth++ ;
306313

307-
//----------------------------------------------------------------------
314+
//------------------------------------------------------------------
308315
// paths += frontier
309316
// Accumulate path counts for vertices at current depth
310-
//----------------------------------------------------------------------
317+
//------------------------------------------------------------------
311318

312-
GRB_TRY (GrB_assign (paths, NULL, GrB_PLUS_FP64, frontier, GrB_ALL, n,
313-
NULL)) ;
319+
GRB_TRY (GrB_assign (paths, NULL, GrB_PLUS_FP64, frontier, GrB_ALL,
320+
n, NULL)) ;
314321

315-
//----------------------------------------------------------------------
322+
//------------------------------------------------------------------
316323
// Search[depth] = structure(frontier)
317324
// Record the frontier structure at current depth
318-
//----------------------------------------------------------------------
325+
//------------------------------------------------------------------
319326

320327
GrB_free (&(Search [depth])) ;
321-
LG_TRY (LAGraph_Vector_Structure (&(Search [depth]), frontier, msg)) ;
328+
LG_TRY (LAGraph_Vector_Structure (&(Search [depth]), frontier,
329+
msg)) ;
322330

323-
//----------------------------------------------------------------------
331+
//------------------------------------------------------------------
324332
// frontier<!paths> = frontier * A
325-
//----------------------------------------------------------------------
333+
//------------------------------------------------------------------
326334

327335
GRB_TRY (LG_SET_FORMAT_HINT (frontier, LG_SPARSE)) ;
328336
GRB_TRY (GrB_vxm (frontier, paths, NULL, LAGraph_plus_first_fp64,
329337
frontier, A, GrB_DESC_RSC )) ;
330338

331-
//----------------------------------------------------------------------
339+
//------------------------------------------------------------------
332340
// Get size of current frontier: frontier_size = nvals(frontier)
333-
//----------------------------------------------------------------------
341+
//------------------------------------------------------------------
334342

335343
last_frontier_size = frontier_size ;
336344
GRB_TRY (GrB_Vector_nvals (&frontier_size, frontier)) ;
337-
}
338345

346+
LG_ASSERT (depth <= n, GrB_PANIC) ;
347+
}
339348

340-
// =========================================================================
341-
// === Betweenness centrality computation phase ============================
342-
// =========================================================================
349+
// =====================================================================
350+
// === Betweenness centrality computation phase ========================
351+
// =====================================================================
343352

344353
// bc_vertex_flow = ones (n, n) ; a full matrix (and stays full)
345-
GRB_TRY (GrB_assign(bc_vertex_flow, NULL, NULL, 0.0, GrB_ALL, n, NULL)) ;
354+
GRB_TRY (GrB_assign(bc_vertex_flow, NULL, NULL, 0.0, GrB_ALL, n, NULL));
346355

347356
GRB_TRY (GrB_Matrix_clear (HalfUpdate)) ;
348357
GRB_TRY (GrB_Matrix_clear (HalfUpdateT)) ;
@@ -352,36 +361,39 @@ int LAGr_EdgeBetweennessCentrality
352361
GRB_TRY (GrB_Vector_clear (I_vec)) ;
353362
GRB_TRY (GrB_Vector_clear (temp_update)) ;
354363

355-
// Backtrack through the BFS and compute centrality updates for each vertex
356-
// GrB_Index fd1_size;
364+
// Backtrack through the BFS and compute centrality updates for each
365+
// vertex
357366

358367
while (depth >= 1)
359368
{
360369
GrB_Vector f_d = Search [depth] ;
361370
GrB_Vector f_d1 = Search [depth - 1] ;
362371

363-
//----------------------------------------------------------------------
372+
//------------------------------------------------------------------
364373
// j<S(depth, :)> = (1 + v) / p
365374
// J = diag(j)
366375
// Compute weighted contributions from current level
367-
//----------------------------------------------------------------------
376+
//------------------------------------------------------------------
377+
378+
GRB_TRY (GrB_eWiseMult(J_vec, f_d, NULL, Add_One_Divide,
379+
bc_vertex_flow, paths, GrB_DESC_RS)) ;
368380

369-
GRB_TRY (GrB_eWiseMult(J_vec, f_d, NULL, Add_One_Divide, bc_vertex_flow, paths, GrB_DESC_RS)) ;
370381
GRB_TRY (GrB_Matrix_diag(&J_matrix, J_vec, 0)) ;
371382

372-
//----------------------------------------------------------------------
383+
//------------------------------------------------------------------
373384
// i<S(depth-1, :)> = p
374385
// I = diag(i)
375386
// Compute weighted contributions from previous level
376-
//----------------------------------------------------------------------
387+
//------------------------------------------------------------------
377388

378-
GRB_TRY (GrB_Vector_extract (I_vec, f_d1, NULL, paths, GrB_ALL, n, GrB_DESC_RS)) ;
389+
GRB_TRY (GrB_Vector_extract (I_vec, f_d1, NULL, paths, GrB_ALL, n,
390+
GrB_DESC_RS)) ;
379391
GRB_TRY (GrB_Matrix_diag(&I_matrix, I_vec, 0)) ;
380392

381-
//----------------------------------------------------------------------
393+
//------------------------------------------------------------------
382394
// Update = I × A × J
383395
// Compute edge updates based on current level weights
384-
//----------------------------------------------------------------------
396+
//------------------------------------------------------------------
385397

386398
double t1 = LAGraph_WallClockTime();
387399
GRB_TRY(GrB_mxm(Fd1A, NULL, NULL, LAGraph_plus_first_fp64,
@@ -396,32 +408,62 @@ int LAGr_EdgeBetweennessCentrality
396408
t2_total += t2;
397409
GRB_TRY (GrB_free (&I_matrix)) ;
398410
GRB_TRY (GrB_free (&J_matrix)) ;
399-
//----------------------------------------------------------------------
400-
// centrality<A> += Update
411+
412+
//------------------------------------------------------------------
413+
// centrality<A,struct> += Update
401414
// Accumulate centrality values for edges
402-
//----------------------------------------------------------------------
415+
//------------------------------------------------------------------
416+
417+
// The centrality and A matrices have the same pattern.
418+
// centrality<centrality,struct> += Update should be fast, since it
419+
// tells GraphBLAS that the pattern of centrality doesn't change.
420+
// No pending tuples or zombies will be added to the matrix.
421+
// However, it currently forces GraphBLAS to make copy of the
422+
// centrality matrix to use as a mask.
403423

404424
#ifdef useAssign
405-
// centrality{A} += Update, using assign
425+
// centrality<A,struct> += Update, using assign
406426
double t3 = LAGraph_WallClockTime();
407427

408428
if (G->kind == LAGraph_ADJACENCY_UNDIRECTED) {
409-
// First divide the Update matrix by 2 for symmetric distribution
410-
GrB_apply(HalfUpdate, NULL, NULL, GrB_DIV_FP64, Update, 2.0, NULL);
429+
// First divide the Update matrix by 2 for symmetric
430+
// distribution
431+
GrB_apply(HalfUpdate, NULL, NULL, GrB_DIV_FP64, Update,
432+
2.0, NULL);
411433

412434
// Create a transposed version of the update
413435
GrB_transpose(HalfUpdateT, NULL, NULL, HalfUpdate, NULL);
414436

415-
// Add the original and transposed matrices to create a symmetric update
416-
GrB_eWiseAdd(SymmetricUpdate, NULL, NULL, GrB_PLUS_FP64, HalfUpdate, HalfUpdateT, NULL);
437+
// Add the original and transposed matrices to create a
438+
// symmetric update
439+
GrB_eWiseAdd(SymmetricUpdate, NULL, NULL, GrB_PLUS_FP64,
440+
HalfUpdate, HalfUpdateT, NULL);
417441

418442
// Apply the symmetric update to the centrality
419-
GRB_TRY(GrB_assign(*centrality, A, GrB_PLUS_FP64, SymmetricUpdate, GrB_ALL, n, GrB_ALL, n, GrB_DESC_S));
443+
#if LG_SUITESPARSE_GRAPHBLAS_V10_2
444+
// This was slow prior to v10.2.0:
445+
// centrality<centrality,struct> += SymmetricUpdate
446+
GRB_TRY(GrB_assign(*centrality, *centrality, GrB_PLUS_FP64,
447+
SymmetricUpdate, GrB_ALL, n, GrB_ALL, n, GrB_DESC_S));
448+
#else
449+
// centrality<A,struct> += SymmetricUpdate
450+
GRB_TRY(GrB_assign(*centrality, A, GrB_PLUS_FP64,
451+
SymmetricUpdate, GrB_ALL, n, GrB_ALL, n, GrB_DESC_S));
452+
#endif
420453

421454
}
422-
else {
423-
GRB_TRY (GrB_assign(*centrality, A, GrB_PLUS_FP64, Update, GrB_ALL, n, GrB_ALL, n,
424-
GrB_DESC_S));
455+
else
456+
{
457+
#if LG_SUITESPARSE_GRAPHBLAS_V10_2
458+
// This was slow prior to v10.2.0:
459+
// centrality<centrality,struct> += Update
460+
GRB_TRY (GrB_assign(*centrality, *centrality, GrB_PLUS_FP64,
461+
Update, GrB_ALL, n, GrB_ALL, n, GrB_DESC_S));
462+
#else
463+
// centrality<A,struct> += Update
464+
GRB_TRY (GrB_assign(*centrality, A, GrB_PLUS_FP64, Update,
465+
GrB_ALL, n, GrB_ALL, n, GrB_DESC_S));
466+
#endif
425467
}
426468

427469
t3 = LAGraph_WallClockTime() - t3;
@@ -430,20 +472,22 @@ int LAGr_EdgeBetweennessCentrality
430472
// TODO: Approx update using ewise add not implemented
431473
// centrality = centrality + Update using eWiseAdd
432474
double t3 = LAGraph_WallClockTime();
433-
GRB_TRY (GrB_eWiseAdd (*centrality, NULL, NULL, GrB_PLUS_FP64, *centrality, Update, NULL));
475+
GRB_TRY (GrB_eWiseAdd (*centrality, NULL, NULL, GrB_PLUS_FP64,
476+
*centrality, Update, NULL));
434477
t3 = LAGraph_WallClockTime() - t3;
435478
t3_total += t3;
436479
#endif
437480

438481

439-
//----------------------------------------------------------------------
482+
//------------------------------------------------------------------
440483
// v = Update +.
441484
// Reduce update matrix to vector for next iteration
442-
//----------------------------------------------------------------------
443-
444-
GRB_TRY (GrB_reduce(temp_update, NULL, NULL, GrB_PLUS_MONOID_FP64, Update, NULL)) ;
445-
GRB_TRY (GrB_eWiseAdd(bc_vertex_flow, NULL, NULL, GrB_PLUS_FP64, bc_vertex_flow, temp_update, NULL)) ;
485+
//------------------------------------------------------------------
446486

487+
GRB_TRY (GrB_reduce(temp_update, NULL, NULL, GrB_PLUS_MONOID_FP64,
488+
Update, NULL)) ;
489+
GRB_TRY (GrB_eWiseAdd(bc_vertex_flow, NULL, NULL, GrB_PLUS_FP64,
490+
bc_vertex_flow, temp_update, NULL)) ;
447491
// 24 d = d − 1
448492
depth-- ;
449493
}
@@ -452,17 +496,13 @@ int LAGr_EdgeBetweennessCentrality
452496

453497
#ifdef debug
454498
printf(" I*A time: %g\n", t1_total);
455-
456499
printf(" (I*A)*J time: %g\n", t2_total);
457-
458500
#ifdef useAssign
459501
printf(" Centrality update using assign time: %g\n", t3_total);
460502
#else
461503
printf(" Centrality update using eWiseAdd time: %g\n", t3_total);
462504
#endif
463-
464-
GxB_print (*centrality, GxB_FULL) ;
465-
505+
// GxB_print (*centrality, GxB_FULL) ;
466506
#endif
467507

468508

‎experimental/benchmark/edgeBetweennessCentrality_demo.c‎

Lines changed: 2 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -124,14 +124,12 @@ int main (int argc, char **argv)
124124
// compute edge betweenness centrality
125125
//--------------------------------------------------------------------------
126126

127-
// LG_SET_BURBLE (true);
128-
127+
// LG_SET_BURBLE (true);
129128
t = LAGraph_WallClockTime ();
130129
LAGRAPH_TRY (LAGr_EdgeBetweennessCentrality (&centrality, G, sources, msg));
131130
t = LAGraph_WallClockTime () - t;
132131
printf ("Time for LAGr_EdgeBetweennessCentrality: %g sec\n", t);
133-
134-
// LG_SET_BURBLE (false);
132+
// LG_SET_BURBLE (false);
135133

136134
//--------------------------------------------------------------------------
137135
// check the results using LG_check_edgeBetweennessCentrality

‎experimental/test/test_edgeBetweennessCentrality.c‎

Lines changed: 13 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -258,9 +258,12 @@ void test_diamonds_ebc (void)
258258
OK (GrB_free (&centrality)) ;
259259

260260
// compute its betweenness centrality with GraphBLAS version
261+
// LG_SET_BURBLE (true) ;
261262
t = LAGraph_WallClockTime() ;
262263
OK (LAGr_EdgeBetweennessCentrality (&centrality, G, NULL, msg)) ;
263264
t = LAGraph_WallClockTime() - t ;
265+
// LG_SET_BURBLE (false) ;
266+
264267
err = difference(centrality, &diamonds_ebc[0][0], 8, 8) ;
265268
printf ("Time for LAGr_EdgeBetweennessCentrality: %g sec\n", t) ;
266269
printf (" diamonds: err: %e (pure GraphBLAS)\n", err) ;
@@ -310,9 +313,11 @@ void test_karate_ebc (void)
310313
OK (GrB_free (&centrality)) ;
311314

312315
// compute its betweenness centrality (GraphBLAS version)
316+
LG_SET_BURBLE (true) ;
313317
t = LAGraph_WallClockTime() ;
314318
OK (LAGr_EdgeBetweennessCentrality (&centrality, G, NULL, msg)) ;
315319
t = LAGraph_WallClockTime() - t ;
320+
// LG_SET_BURBLE (false) ;
316321
err = difference(centrality, &karate_ebc[0][0], 34, 34) ;
317322
printf (" Time for LAGr_EdgeBetweennessCentrality: %g sec\n", t) ;
318323
printf (" karate: err: %e (GraphBLAS version)\n", err) ;
@@ -369,10 +374,12 @@ void test_many(void)
369374
printf ("\n\n%s (%" PRIu64 " nodes, %" PRIu64 " edges)\n", files[i], n, nedges) ;
370375

371376
// compute its betweenness centrality (GraphBLAS version)
377+
// LG_SET_BURBLE (true) ;
372378
double t = LAGraph_WallClockTime() ;
373379
OK(LAGr_EdgeBetweennessCentrality(&centrality, G, NULL, msg));
374380
t = LAGraph_WallClockTime() - t ;
375381
printf (" Time for LAGr_EdgeBetweennessCentrality: %g sec\n", t) ;
382+
// LG_SET_BURBLE (false) ;
376383

377384
// compute its betweenness centrality (C version)
378385
t = LAGraph_WallClockTime() ;
@@ -450,9 +457,11 @@ void test_diamonds_ebc_approx (void)
450457
OK (GrB_free (&centrality)) ;
451458

452459
// compute its betweenness centrality with GraphBLAS version
460+
// LG_SET_BURBLE (true) ;
453461
t = LAGraph_WallClockTime() ;
454462
OK (LAGr_EdgeBetweennessCentrality (&centrality, G, sources, msg)) ;
455463
t = LAGraph_WallClockTime() - t ;
464+
// LG_SET_BURBLE (false) ;
456465
err = difference(centrality, &diamonds_ebc_approx[0][0], 8, 8) ;
457466
printf ("Time for LAGr_EdgeBetweennessCentrality: %g sec\n", t) ;
458467
printf (" diamonds: err: %e (pure GraphBLAS)\n", err) ;
@@ -518,9 +527,11 @@ void test_karate_ebc_approx (void)
518527
OK (GrB_free (&centrality)) ;
519528

520529
// compute its betweenness centrality (GraphBLAS version)
530+
// LG_SET_BURBLE (true) ;
521531
t = LAGraph_WallClockTime() ;
522532
OK (LAGr_EdgeBetweennessCentrality (&centrality, G, sources, msg)) ;
523533
t = LAGraph_WallClockTime() - t ;
534+
// LG_SET_BURBLE (false) ;
524535
err = difference(centrality, &karate_ebc_approx[0][0], 34, 34) ;
525536
printf (" Time for LAGr_EdgeBetweennessCentrality: %g sec\n", t) ;
526537
printf (" karate: err: %e (GraphBLAS version)\n", err) ;
@@ -602,10 +613,12 @@ void test_many_approx(void)
602613
OK (LAGraph_Free ((void **) &used, msg)) ;
603614

604615
// compute its betweenness centrality (GraphBLAS version)
616+
// LG_SET_BURBLE (true) ;
605617
t = LAGraph_WallClockTime() ;
606618
OK(LAGr_EdgeBetweennessCentrality(&centrality, G, randomSources, msg));
607619
t = LAGraph_WallClockTime() - t ;
608620
printf (" Time for LAGr_EdgeBetweennessCentrality: %g sec\n", t) ;
621+
// LG_SET_BURBLE (false) ;
609622

610623
// compute its betweenness centrality (C version)
611624
t = LAGraph_WallClockTime() ;

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