#23236 --changed-since prohibitivley slow in large python heavy repositories Issue created by cburroughs The point of

--changed-since

is to do less work. But there are real world reports of the

--changed-since

taking multiple minutes even on beefy CI machines, which is large fraction of the entire build time. "This performance bug is introducing 3-4m delay to our pipelines right now which represents roughly 30-40% of a build pipeline." Consolidating several other discussions: • https://chat.pantsbuild.org/t/28899655/topic • https://chat.pantsbuild.org/t/26992142/topic • https://chat.pantsbuild.org/t/30201298/does-anyone-in-the-pants-community-accept-bountys-for-bug-fi • #23224 • #23228 In #23228 @jasonwbarnett created a synthetic reproduction at https://github.com/altana-ai/pants-changed-dependents-perf-repro Note: To the extent the problem boils down to "dependency inference", see also #18911 For memory and large number of targets see #22393 pantsbuild/pants