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…arallelLeidenView Replace per-visit std::unordered_map hashing with InducedSubgraphView-style flat techniques: - CoarsenedGraphView::computeNeighbors stages (supernode, weight) pairs into a thread-local buffer, sorts, and combines runs. Removes hash-table ops and per-call bucket allocations; output is deterministic. - ParallelLeidenView::parallelMove stages (community, weight) pairs once per visit, sort-combines into parallel pointers/cutVals vectors, and uses binary search for the current-community cut. Reusable per-thread buffers cut malloc/free churn; single forNeighborsOf pass halves view re-aggregation in the move phase. - ParallelLeidenView::parallelRefine uses Aux::flat_map for cutWeights (small refinement neighborhoods favor binary search over hashing).
Scope the CoarsenedGraphView aggregation buffer to the phase: reusable thread-local scratch within a move/refine phase, released (shrink_to_fit) via CoarsenedGraphView::releaseThreadScratch() at each phase boundary in ParallelLeidenView::parallelMove/parallelRefine. A giant-supernode high-water mark from one level can no longer leak into the next.
adsharma
added this pull request to stack #79
September 14, 2026 21:56
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Replace per-visit std::unordered_map hashing with flat sort-combine techniques (see stacked PR for eager cache follow-up).
Tests: networkit_tests eiden:oarsen:nducedSubgraph 46/46 passed.