Fixes the performance issue in Project()
#2383
Merged
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What do these changes do?
ProjectToSimple()
requires scan all edges to establish the new offset ranges. The previous implements runs slow (slower than scan edges for many times in pagerank) becauseO(E)
.getRangeOfLabel
takesstd::shared_ptr
as argument, the shared ptr would be constructed and destructed forO(V)
times.This PR optimize the implementation. Benchmark shows that it improve the
Project()
operation from2~3 seconds
to0.02~0.1 seconds
(consider the overhead of creating threads for parallelism) on an internal datasets. (PageRank requires about0.02~0.03 seconds
to scan the edges).Related issue number
Part of #1300