File size: 8,350 Bytes
d844fc8 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 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 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 | #include <algorithm>
#include <chrono>
#include <cstdint>
#include <fstream>
#include <iostream>
#include <limits>
#include <queue>
#include <sstream>
#include <string>
#include <utility>
#include <vector>
#include "velographx/incremental/bfs.hpp"
#include "velographx/storage/dynamic_graph.hpp"
namespace {
using Edge = std::pair<velographx::VertexId, velographx::VertexId>;
std::vector<Edge> read_edges(const std::string& path, std::size_t& vertices) {
std::ifstream in(path);
if (!in) throw std::runtime_error("cannot open edge list: " + path);
std::vector<Edge> edges;
std::string line;
std::uint64_t max_vertex = 0;
bool saw = false;
while (std::getline(in, line)) {
if (line.empty() || line[0] == '#') continue;
std::istringstream row(line);
std::uint64_t u = 0, v = 0;
if (!(row >> u >> v)) continue;
if (u > std::numeric_limits<velographx::VertexId>::max() ||
v > std::numeric_limits<velographx::VertexId>::max()) {
throw std::runtime_error("vertex id exceeds VeloGraphX VertexId range");
}
edges.emplace_back(static_cast<velographx::VertexId>(u),
static_cast<velographx::VertexId>(v));
max_vertex = std::max(max_vertex, std::max(u, v));
saw = true;
}
vertices = saw ? static_cast<std::size_t>(max_vertex + 1) : 0;
return edges;
}
std::vector<std::uint32_t> full_bfs(const velographx::DynamicGraph& graph,
velographx::VertexId source) {
const auto unreachable = std::numeric_limits<std::uint32_t>::max();
std::vector<std::uint32_t> dist(graph.vertex_count(), unreachable);
if (source >= graph.vertex_count()) return dist;
std::queue<velographx::VertexId> q;
dist[source] = 0;
q.push(source);
while (!q.empty()) {
const auto u = q.front();
q.pop();
for (const auto v : graph.neighbors(u)) {
if (dist[v] == unreachable) {
dist[v] = dist[u] + 1;
q.push(v);
}
}
}
return dist;
}
std::vector<std::uint64_t> layer_counts(const std::vector<std::uint32_t>& dist) {
const auto unreachable = std::numeric_limits<std::uint32_t>::max();
std::uint32_t max_depth = 0;
for (const auto d : dist) if (d != unreachable) max_depth = std::max(max_depth, d);
std::vector<std::uint64_t> counts(static_cast<std::size_t>(max_depth) + 1, 0);
for (const auto d : dist) if (d != unreachable) ++counts[d];
return counts;
}
velographx::UpdateBatch make_batch(const std::vector<Edge>& edges,
std::size_t imported_edges,
std::size_t local_begin,
std::size_t local_end) {
velographx::UpdateBatch updates;
updates.updates.reserve((local_end - local_begin) * 2);
for (std::size_t i = local_begin; i < local_end; ++i) {
updates.add(edges[i].first, edges[i].second);
}
for (std::size_t i = local_begin; i < local_end; ++i) {
const auto remove_index = i - imported_edges;
updates.remove(edges[remove_index].first, edges[remove_index].second);
}
return updates;
}
void print_u64_array(const std::vector<std::uint64_t>& values) {
std::cout << '[';
for (std::size_t i = 0; i < values.size(); ++i) {
if (i) std::cout << ',';
std::cout << values[i];
}
std::cout << ']';
}
} // namespace
int main(int argc, char** argv) {
if (argc != 5) {
std::cerr << "usage: " << argv[0] << " edge_list root imported_rate batch_size\n";
return 2;
}
const std::string path = argv[1];
const auto root64 = std::stoull(argv[2]);
const double imported_rate = std::stod(argv[3]);
const std::size_t batch_size = std::stoull(argv[4]);
if (!(imported_rate > 0.0 && imported_rate < 1.0) || batch_size == 0 ||
root64 > std::numeric_limits<velographx::VertexId>::max()) {
std::cerr << "invalid arguments\n";
return 2;
}
const auto root = static_cast<velographx::VertexId>(root64);
std::size_t vertices = 0;
const auto edges = read_edges(path, vertices);
const auto imported_edges = static_cast<std::size_t>(edges.size() * imported_rate);
if (edges.empty() || imported_edges == 0 || imported_edges >= edges.size()) {
std::cerr << "edge list/imported rate leaves no streaming window\n";
return 2;
}
std::vector<Edge> initial(edges.begin(), edges.begin() + imported_edges);
// Current deletion-aware policy.
velographx::DynamicGraph graph(vertices, true);
graph.bulk_load_edges(initial);
velographx::IncrementalBFS bfs(graph, root);
std::size_t batches = 0;
std::size_t operations = 0;
std::size_t deletion_candidates = 0;
std::size_t affected_vertices = 0;
std::size_t full_recompute_batches = 0;
const auto incremental_begin = std::chrono::steady_clock::now();
for (std::size_t local_begin = imported_edges; local_begin < edges.size(); local_begin += batch_size) {
const auto local_end = std::min(local_begin + batch_size, edges.size());
auto updates = make_batch(edges, imported_edges, local_begin, local_end);
operations += updates.updates.size();
bfs.apply(updates);
deletion_candidates += bfs.last_deletion_candidates();
affected_vertices += bfs.last_affected_vertices();
full_recompute_batches += bfs.last_used_full_recompute() ? 1 : 0;
++batches;
}
const auto incremental_end = std::chrono::steady_clock::now();
const double wall_us = std::chrono::duration<double, std::micro>(incremental_end - incremental_begin).count();
const auto reference = full_bfs(graph, root);
const bool correct = reference == bfs.distances();
// Exact historical policy: every deletion-containing streaming batch mutates
// the graph and then rebuilds BFS from scratch. This is measured on the same
// edge stream in the same process to isolate the gain from deletion repair.
velographx::DynamicGraph legacy_graph(vertices, true);
legacy_graph.bulk_load_edges(initial);
velographx::IncrementalBFS legacy_bfs(legacy_graph, root);
const auto legacy_begin = std::chrono::steady_clock::now();
for (std::size_t local_begin = imported_edges; local_begin < edges.size(); local_begin += batch_size) {
const auto local_end = std::min(local_begin + batch_size, edges.size());
auto updates = make_batch(edges, imported_edges, local_begin, local_end);
legacy_graph.apply(updates);
legacy_bfs.recompute();
}
const auto legacy_end = std::chrono::steady_clock::now();
const double legacy_wall_us = std::chrono::duration<double, std::micro>(legacy_end - legacy_begin).count();
const bool legacy_correct = legacy_bfs.distances() == reference;
const auto layers = layer_counts(bfs.distances());
std::size_t visited = 0;
for (const auto count : layers) visited += count;
std::cout << "{\"schema_version\":2,"
<< "\"artifact_type\":\"velographx-risgraph-bfs-comparison\","
<< "\"correct\":" << (correct ? "true" : "false") << ','
<< "\"legacy_correct\":" << (legacy_correct ? "true" : "false") << ','
<< "\"directed\":true,"
<< "\"vertices\":" << vertices << ','
<< "\"source_edges\":" << edges.size() << ','
<< "\"initial_edges\":" << imported_edges << ','
<< "\"final_edges\":" << graph.edge_count_directed() << ','
<< "\"root\":" << root64 << ','
<< "\"imported_rate\":" << imported_rate << ','
<< "\"batch_size\":" << batch_size << ','
<< "\"batches\":" << batches << ','
<< "\"update_operations\":" << operations << ','
<< "\"deletion_candidates\":" << deletion_candidates << ','
<< "\"affected_vertices\":" << affected_vertices << ','
<< "\"full_recompute_batches\":" << full_recompute_batches << ','
<< "\"wall_us\":" << wall_us << ','
<< "\"wall_mean_us\":" << (batches ? wall_us / batches : 0.0) << ','
<< "\"legacy_full_recompute_wall_us\":" << legacy_wall_us << ','
<< "\"legacy_full_recompute_mean_us\":" << (batches ? legacy_wall_us / batches : 0.0) << ','
<< "\"deletion_repair_speedup_over_legacy\":" << (wall_us ? legacy_wall_us / wall_us : 0.0) << ','
<< "\"visited_vertices\":" << visited << ','
<< "\"layer_counts\":";
print_u64_array(layers);
std::cout << "}\n";
return (correct && legacy_correct) ? 0 : 1;
}
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