neighbor_sample_cpu.cpp 17.4 KB
Newer Older
rusty1s's avatar
rusty1s committed
1
2
3
4
#include "neighbor_sample_cpu.h"

#include "utils.h"

5
6
#include "parallel_hashmap/phmap.h"

rusty1s's avatar
rusty1s committed
7
8
9
10
#ifdef _WIN32
#include <process.h>
#endif

rusty1s's avatar
rusty1s committed
11
12
13
14
15
16
17
18
19
20
21
using namespace std;

namespace {

template <bool replace, bool directed>
tuple<torch::Tensor, torch::Tensor, torch::Tensor, torch::Tensor>
sample(const torch::Tensor &colptr, const torch::Tensor &row,
       const torch::Tensor &input_node, const vector<int64_t> num_neighbors) {

  // Initialize some data structures for the sampling process:
  vector<int64_t> samples;
22
  phmap::flat_hash_map<int64_t, int64_t> to_local_node;
rusty1s's avatar
rusty1s committed
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47

  auto *colptr_data = colptr.data_ptr<int64_t>();
  auto *row_data = row.data_ptr<int64_t>();
  auto *input_node_data = input_node.data_ptr<int64_t>();

  for (int64_t i = 0; i < input_node.numel(); i++) {
    const auto &v = input_node_data[i];
    samples.push_back(v);
    to_local_node.insert({v, i});
  }

  vector<int64_t> rows, cols, edges;

  int64_t begin = 0, end = samples.size();
  for (int64_t ell = 0; ell < (int64_t)num_neighbors.size(); ell++) {
    const auto &num_samples = num_neighbors[ell];
    for (int64_t i = begin; i < end; i++) {
      const auto &w = samples[i];
      const auto &col_start = colptr_data[w];
      const auto &col_end = colptr_data[w + 1];
      const auto col_count = col_end - col_start;

      if (col_count == 0)
        continue;

rusty1s's avatar
bugfix  
rusty1s committed
48
49
      if ((num_samples < 0) || (!replace && (num_samples >= col_count))) {
        for (int64_t offset = col_start; offset < col_end; offset++) {
rusty1s's avatar
rusty1s committed
50
51
52
53
54
55
56
57
58
59
          const int64_t &v = row_data[offset];
          const auto res = to_local_node.insert({v, samples.size()});
          if (res.second)
            samples.push_back(v);
          if (directed) {
            cols.push_back(i);
            rows.push_back(res.first->second);
            edges.push_back(offset);
          }
        }
rusty1s's avatar
bugfix  
rusty1s committed
60
61
      } else if (replace) {
        for (int64_t j = 0; j < num_samples; j++) {
62
          const int64_t offset = col_start + uniform_randint(col_count);
rusty1s's avatar
rusty1s committed
63
64
65
66
67
68
69
70
71
72
73
74
75
          const int64_t &v = row_data[offset];
          const auto res = to_local_node.insert({v, samples.size()});
          if (res.second)
            samples.push_back(v);
          if (directed) {
            cols.push_back(i);
            rows.push_back(res.first->second);
            edges.push_back(offset);
          }
        }
      } else {
        unordered_set<int64_t> rnd_indices;
        for (int64_t j = col_count - num_samples; j < col_count; j++) {
76
          int64_t rnd = uniform_randint(j);
rusty1s's avatar
rusty1s committed
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
          if (!rnd_indices.insert(rnd).second) {
            rnd = j;
            rnd_indices.insert(j);
          }
          const int64_t offset = col_start + rnd;
          const int64_t &v = row_data[offset];
          const auto res = to_local_node.insert({v, samples.size()});
          if (res.second)
            samples.push_back(v);
          if (directed) {
            cols.push_back(i);
            rows.push_back(res.first->second);
            edges.push_back(offset);
          }
        }
      }
    }
    begin = end, end = samples.size();
  }

  if (!directed) {
98
    phmap::flat_hash_map<int64_t, int64_t>::iterator iter;
rusty1s's avatar
rusty1s committed
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
    for (int64_t i = 0; i < (int64_t)samples.size(); i++) {
      const auto &w = samples[i];
      const auto &col_start = colptr_data[w];
      const auto &col_end = colptr_data[w + 1];
      for (int64_t offset = col_start; offset < col_end; offset++) {
        const auto &v = row_data[offset];
        iter = to_local_node.find(v);
        if (iter != to_local_node.end()) {
          rows.push_back(iter->second);
          cols.push_back(i);
          edges.push_back(offset);
        }
      }
    }
  }

  return make_tuple(from_vector<int64_t>(samples), from_vector<int64_t>(rows),
                    from_vector<int64_t>(cols), from_vector<int64_t>(edges));
}

119
inline bool satisfy_time(const c10::Dict<node_t, torch::Tensor> &node_time_dict,
120
121
                         const node_t &src_node_type, int64_t dst_time,
                         int64_t src_node) {
122
123
  try {
    // Check whether src -> dst obeys the time constraint
124
125
    const torch::Tensor &src_node_time = node_time_dict.at(src_node_type);
    return src_node_time.data_ptr<int64_t>()[src_node] <= dst_time;
126
127
  } catch (const std::out_of_range& e) {
    // If no time is given, fall back to normal sampling
Rex Ying's avatar
Rex Ying committed
128
129
130
131
132
    return true;
  }
}

template <bool replace, bool directed, bool temporal>
rusty1s's avatar
bugfix  
rusty1s committed
133
134
135
tuple<c10::Dict<node_t, torch::Tensor>, c10::Dict<rel_t, torch::Tensor>,
      c10::Dict<rel_t, torch::Tensor>, c10::Dict<rel_t, torch::Tensor>>
hetero_sample(const vector<node_t> &node_types,
Matthias Fey's avatar
Matthias Fey committed
136
137
138
139
140
              const vector<edge_t> &edge_types,
              const c10::Dict<rel_t, torch::Tensor> &colptr_dict,
              const c10::Dict<rel_t, torch::Tensor> &row_dict,
              const c10::Dict<node_t, torch::Tensor> &input_node_dict,
              const c10::Dict<rel_t, vector<int64_t>> &num_neighbors_dict,
141
142
143
              const c10::Dict<node_t, torch::Tensor> &node_time_dict,
              const int64_t num_hops) {

rusty1s's avatar
rusty1s committed
144
145
146
147
148
149
  // Create a mapping to convert single string relations to edge type triplets:
  unordered_map<rel_t, edge_t> to_edge_type;
  for (const auto &k : edge_types)
    to_edge_type[get<0>(k) + "__" + get<1>(k) + "__" + get<2>(k)] = k;

  // Initialize some data structures for the sampling process:
Rex Ying's avatar
Rex Ying committed
150
151
152
153
154
155
156
157
158
  unordered_map<node_t, vector<int64_t>> samples_dict;
  unordered_map<node_t, unordered_map<int64_t, int64_t>> to_local_node_dict;
  unordered_map<node_t, vector<int64_t>> root_time_dict;
  for (const auto &node_type : node_types) {
    samples_dict[node_type];
    to_local_node_dict[node_type];
    root_time_dict[node_type];
  }

159
160
161
162
163
164
165
166
  unordered_map<rel_t, vector<int64_t>> rows_dict, cols_dict, edges_dict;
  for (const auto &kv : colptr_dict) {
    const auto &rel_type = kv.key();
    rows_dict[rel_type];
    cols_dict[rel_type];
    edges_dict[rel_type];
  }

rusty1s's avatar
rusty1s committed
167
168
169
  // Add the input nodes to the output nodes:
  for (const auto &kv : input_node_dict) {
    const auto &node_type = kv.key();
Michał Marcinkiewicz's avatar
Michał Marcinkiewicz committed
170
    const torch::Tensor &input_node = kv.value();
rusty1s's avatar
rusty1s committed
171
    const auto *input_node_data = input_node.data_ptr<int64_t>();
172

Matthias Fey's avatar
Matthias Fey committed
173
    int64_t *node_time_data;
Rex Ying's avatar
Rex Ying committed
174
    if (temporal) {
175
      const torch::Tensor &node_time = node_time_dict.at(node_type);
Matthias Fey's avatar
Matthias Fey committed
176
      node_time_data = node_time.data_ptr<int64_t>();
Rex Ying's avatar
Rex Ying committed
177
    }
rusty1s's avatar
rusty1s committed
178
179
180

    auto &samples = samples_dict.at(node_type);
    auto &to_local_node = to_local_node_dict.at(node_type);
Rex Ying's avatar
Rex Ying committed
181
    auto &root_time = root_time_dict.at(node_type);
rusty1s's avatar
rusty1s committed
182
183
184
185
    for (int64_t i = 0; i < input_node.numel(); i++) {
      const auto &v = input_node_data[i];
      samples.push_back(v);
      to_local_node.insert({v, i});
186
      if (temporal)
Rex Ying's avatar
Rex Ying committed
187
        root_time.push_back(node_time_data[v]);
rusty1s's avatar
rusty1s committed
188
189
190
191
192
193
194
195
196
197
198
199
200
    }
  }

  unordered_map<node_t, pair<int64_t, int64_t>> slice_dict;
  for (const auto &kv : samples_dict)
    slice_dict[kv.first] = {0, kv.second.size()};

  for (int64_t ell = 0; ell < num_hops; ell++) {
    for (const auto &kv : num_neighbors_dict) {
      const auto &rel_type = kv.key();
      const auto &edge_type = to_edge_type[rel_type];
      const auto &src_node_type = get<0>(edge_type);
      const auto &dst_node_type = get<2>(edge_type);
rusty1s's avatar
bugfix  
rusty1s committed
201
      const auto num_samples = kv.value()[ell];
rusty1s's avatar
rusty1s committed
202
203
204
205
      const auto &dst_samples = samples_dict.at(dst_node_type);
      auto &src_samples = samples_dict.at(src_node_type);
      auto &to_local_src_node = to_local_node_dict.at(src_node_type);

206
207
208
209
      const torch::Tensor &colptr = colptr_dict.at(rel_type);
      const auto *colptr_data = colptr.data_ptr<int64_t>();
      const torch::Tensor &row = row_dict.at(rel_type);
      const auto *row_data = row.data_ptr<int64_t>();
rusty1s's avatar
rusty1s committed
210
211
212
213
214

      auto &rows = rows_dict.at(rel_type);
      auto &cols = cols_dict.at(rel_type);
      auto &edges = edges_dict.at(rel_type);

215
      // For temporal sampling, sampled nodes cannot have a timestamp greater
216
      // than the timestamp of the root nodes:
Rex Ying's avatar
Rex Ying committed
217
218
219
      const auto &dst_root_time = root_time_dict.at(dst_node_type);
      auto &src_root_time = root_time_dict.at(src_node_type);

220
221
      const auto &begin = slice_dict.at(dst_node_type).first;
      const auto &end = slice_dict.at(dst_node_type).second;
rusty1s's avatar
rusty1s committed
222
223
      for (int64_t i = begin; i < end; i++) {
        const auto &w = dst_samples[i];
224
225
226
        int64_t dst_time = 0;
        if (temporal)
          dst_time = dst_root_time[i];
rusty1s's avatar
rusty1s committed
227
228
229
230
231
232
233
        const auto &col_start = colptr_data[w];
        const auto &col_end = colptr_data[w + 1];
        const auto col_count = col_end - col_start;

        if (col_count == 0)
          continue;

rusty1s's avatar
bugfix  
rusty1s committed
234
        if ((num_samples < 0) || (!replace && (num_samples >= col_count))) {
235
          // Select all neighbors:
rusty1s's avatar
bugfix  
rusty1s committed
236
          for (int64_t offset = col_start; offset < col_end; offset++) {
rusty1s's avatar
rusty1s committed
237
            const int64_t &v = row_data[offset];
Rex Ying's avatar
Rex Ying committed
238
            if (temporal) {
239
240
              if (!satisfy_time(node_time_dict, src_node_type, dst_time, v))
                continue;
241
242
243
244
              // force disjoint of computation tree
              // note that the sampling always needs to have directed=True
              // for temporal case
              // to_local_src_node is not used for temporal / directed case
245
              const int64_t sample_idx = src_samples.size();
rusty1s's avatar
rusty1s committed
246
              src_samples.push_back(v);
247
              src_root_time.push_back(dst_time);
rusty1s's avatar
rusty1s committed
248
              cols.push_back(i);
249
              rows.push_back(sample_idx);
rusty1s's avatar
rusty1s committed
250
              edges.push_back(offset);
251
252
253
254
255
256
257
258
259
            } else {
              const auto res = to_local_src_node.insert({v, src_samples.size()});
              if (res.second)
                src_samples.push_back(v);
              if (directed) {
                cols.push_back(i);
                rows.push_back(res.first->second);
                edges.push_back(offset);
              }
rusty1s's avatar
rusty1s committed
260
261
            }
          }
rusty1s's avatar
bugfix  
rusty1s committed
262
        } else if (replace) {
263
          // Sample with replacement:
Rex Ying's avatar
Rex Ying committed
264
265
          int64_t num_neighbors = 0;
          while (num_neighbors < num_samples) {
266
            const int64_t offset = col_start + uniform_randint(col_count);
rusty1s's avatar
rusty1s committed
267
            const int64_t &v = row_data[offset];
Rex Ying's avatar
Rex Ying committed
268
            if (temporal) {
269
270
271
              // TODO Infinity loop if no neighbor satisfies time constraint:
              if (!satisfy_time(node_time_dict, src_node_type, dst_time, v))
                continue;
272
273
274
              // force disjoint of computation tree
              // note that the sampling always needs to have directed=True
              // for temporal case
275
              const int64_t sample_idx = src_samples.size();
rusty1s's avatar
rusty1s committed
276
              src_samples.push_back(v);
277
              src_root_time.push_back(dst_time);
rusty1s's avatar
rusty1s committed
278
              cols.push_back(i);
279
              rows.push_back(sample_idx);
rusty1s's avatar
rusty1s committed
280
              edges.push_back(offset);
281
282
283
284
285
286
287
288
289
            } else {
              const auto res = to_local_src_node.insert({v, src_samples.size()});
              if (res.second)
                src_samples.push_back(v);
              if (directed) {
                cols.push_back(i);
                rows.push_back(res.first->second);
                edges.push_back(offset);
              }
rusty1s's avatar
rusty1s committed
290
            }
Rex Ying's avatar
Rex Ying committed
291
            num_neighbors += 1;
rusty1s's avatar
rusty1s committed
292
293
          }
        } else {
294
          // Sample without replacement:
rusty1s's avatar
rusty1s committed
295
296
          unordered_set<int64_t> rnd_indices;
          for (int64_t j = col_count - num_samples; j < col_count; j++) {
297
            int64_t rnd = uniform_randint(j);
rusty1s's avatar
rusty1s committed
298
299
300
301
302
303
            if (!rnd_indices.insert(rnd).second) {
              rnd = j;
              rnd_indices.insert(j);
            }
            const int64_t offset = col_start + rnd;
            const int64_t &v = row_data[offset];
Rex Ying's avatar
Rex Ying committed
304
            if (temporal) {
305
306
              if (!satisfy_time(node_time_dict, src_node_type, dst_time, v))
                continue;
307
308
309
              // force disjoint of computation tree
              // note that the sampling always needs to have directed=True
              // for temporal case
310
              const int64_t sample_idx = src_samples.size();
rusty1s's avatar
rusty1s committed
311
              src_samples.push_back(v);
312
              src_root_time.push_back(dst_time);
rusty1s's avatar
rusty1s committed
313
              cols.push_back(i);
314
              rows.push_back(sample_idx);
rusty1s's avatar
rusty1s committed
315
              edges.push_back(offset);
316
317
318
319
320
321
322
323
324
            } else {
              const auto res = to_local_src_node.insert({v, src_samples.size()});
              if (res.second)
                src_samples.push_back(v);
              if (directed) {
                cols.push_back(i);
                rows.push_back(res.first->second);
                edges.push_back(offset);
              }
rusty1s's avatar
rusty1s committed
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
            }
          }
        }
      }
    }

    for (const auto &kv : samples_dict) {
      slice_dict[kv.first] = {slice_dict.at(kv.first).second, kv.second.size()};
    }
  }

  if (!directed) { // Construct the subgraph among the sampled nodes:
    unordered_map<int64_t, int64_t>::iterator iter;
    for (const auto &kv : colptr_dict) {
      const auto &rel_type = kv.key();
      const auto &edge_type = to_edge_type[rel_type];
      const auto &src_node_type = get<0>(edge_type);
      const auto &dst_node_type = get<2>(edge_type);
      const auto &dst_samples = samples_dict.at(dst_node_type);
      auto &to_local_src_node = to_local_node_dict.at(src_node_type);

Michał Marcinkiewicz's avatar
Michał Marcinkiewicz committed
346
      const auto *colptr_data = ((torch::Tensor)kv.value()).data_ptr<int64_t>();
347
348
      const auto *row_data =
          ((torch::Tensor)row_dict.at(rel_type)).data_ptr<int64_t>();
rusty1s's avatar
rusty1s committed
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395

      auto &rows = rows_dict.at(rel_type);
      auto &cols = cols_dict.at(rel_type);
      auto &edges = edges_dict.at(rel_type);

      for (int64_t i = 0; i < (int64_t)dst_samples.size(); i++) {
        const auto &w = dst_samples[i];
        const auto &col_start = colptr_data[w];
        const auto &col_end = colptr_data[w + 1];
        for (int64_t offset = col_start; offset < col_end; offset++) {
          const auto &v = row_data[offset];
          iter = to_local_src_node.find(v);
          if (iter != to_local_src_node.end()) {
            rows.push_back(iter->second);
            cols.push_back(i);
            edges.push_back(offset);
          }
        }
      }
    }
  }

  return make_tuple(from_vector<node_t, int64_t>(samples_dict),
                    from_vector<rel_t, int64_t>(rows_dict),
                    from_vector<rel_t, int64_t>(cols_dict),
                    from_vector<rel_t, int64_t>(edges_dict));
}

} // namespace

tuple<torch::Tensor, torch::Tensor, torch::Tensor, torch::Tensor>
neighbor_sample_cpu(const torch::Tensor &colptr, const torch::Tensor &row,
                    const torch::Tensor &input_node,
                    const vector<int64_t> num_neighbors, const bool replace,
                    const bool directed) {

  if (replace && directed) {
    return sample<true, true>(colptr, row, input_node, num_neighbors);
  } else if (replace && !directed) {
    return sample<true, false>(colptr, row, input_node, num_neighbors);
  } else if (!replace && directed) {
    return sample<false, true>(colptr, row, input_node, num_neighbors);
  } else {
    return sample<false, false>(colptr, row, input_node, num_neighbors);
  }
}

rusty1s's avatar
bugfix  
rusty1s committed
396
397
tuple<c10::Dict<node_t, torch::Tensor>, c10::Dict<rel_t, torch::Tensor>,
      c10::Dict<rel_t, torch::Tensor>, c10::Dict<rel_t, torch::Tensor>>
rusty1s's avatar
rusty1s committed
398
hetero_neighbor_sample_cpu(
rusty1s's avatar
bugfix  
rusty1s committed
399
    const vector<node_t> &node_types, const vector<edge_t> &edge_types,
rusty1s's avatar
rusty1s committed
400
401
402
    const c10::Dict<rel_t, torch::Tensor> &colptr_dict,
    const c10::Dict<rel_t, torch::Tensor> &row_dict,
    const c10::Dict<node_t, torch::Tensor> &input_node_dict,
rusty1s's avatar
bugfix  
rusty1s committed
403
    const c10::Dict<rel_t, vector<int64_t>> &num_neighbors_dict,
rusty1s's avatar
rusty1s committed
404
405
    const int64_t num_hops, const bool replace, const bool directed) {

406
407
  c10::Dict<node_t, torch::Tensor> node_time_dict; // Empty dictionary.

rusty1s's avatar
rusty1s committed
408
  if (replace && directed) {
409
410
411
    return hetero_sample<true, true, false>(
        node_types, edge_types, colptr_dict, row_dict, input_node_dict,
        num_neighbors_dict, node_time_dict, num_hops);
Rex Ying's avatar
Rex Ying committed
412
  } else if (replace && !directed) {
413
    return hetero_sample<true, false, false>(
Matthias Fey's avatar
Matthias Fey committed
414
        node_types, edge_types, colptr_dict, row_dict, input_node_dict,
415
        num_neighbors_dict, node_time_dict, num_hops);
Rex Ying's avatar
Rex Ying committed
416
  } else if (!replace && directed) {
417
    return hetero_sample<false, true, false>(
Matthias Fey's avatar
Matthias Fey committed
418
        node_types, edge_types, colptr_dict, row_dict, input_node_dict,
419
        num_neighbors_dict, node_time_dict, num_hops);
Rex Ying's avatar
Rex Ying committed
420
  } else {
421
    return hetero_sample<false, false, false>(
Matthias Fey's avatar
Matthias Fey committed
422
        node_types, edge_types, colptr_dict, row_dict, input_node_dict,
423
        num_neighbors_dict, node_time_dict, num_hops);
Rex Ying's avatar
Rex Ying committed
424
425
426
427
428
  }
}

tuple<c10::Dict<node_t, torch::Tensor>, c10::Dict<rel_t, torch::Tensor>,
      c10::Dict<rel_t, torch::Tensor>, c10::Dict<rel_t, torch::Tensor>>
429
hetero_temporal_neighbor_sample_cpu(
Rex Ying's avatar
Rex Ying committed
430
431
432
433
434
435
436
    const vector<node_t> &node_types, const vector<edge_t> &edge_types,
    const c10::Dict<rel_t, torch::Tensor> &colptr_dict,
    const c10::Dict<rel_t, torch::Tensor> &row_dict,
    const c10::Dict<node_t, torch::Tensor> &input_node_dict,
    const c10::Dict<rel_t, vector<int64_t>> &num_neighbors_dict,
    const c10::Dict<node_t, torch::Tensor> &node_time_dict,
    const int64_t num_hops, const bool replace, const bool directed) {
437
  AT_ASSERTM(directed, "Temporal sampling requires 'directed' sampling");
438
439
440
441
442
443
444
  if (replace) {
    // We assume that directed = True for temporal sampling
    // The current implementation uses disjoint computation trees
    // to tackle the case of the same node sampled having different
    // root time constraint.
    // In future, we could extend to directed = False case,
    // allowing additional edges within each computation tree.
Rex Ying's avatar
Rex Ying committed
445
    return hetero_sample<true, true, true>(
Matthias Fey's avatar
Matthias Fey committed
446
        node_types, edge_types, colptr_dict, row_dict, input_node_dict,
447
        num_neighbors_dict, node_time_dict, num_hops);
rusty1s's avatar
rusty1s committed
448
  } else {
449
    return hetero_sample<false, true, true>(
Matthias Fey's avatar
Matthias Fey committed
450
        node_types, edge_types, colptr_dict, row_dict, input_node_dict,
451
        num_neighbors_dict, node_time_dict, num_hops);
rusty1s's avatar
rusty1s committed
452
453
  }
}