nvidia / nccl
Optimized primitives for collective multi-GPU communication
github.com/nvidia/ncclIndexed at 9287574Up to date with upstream
About this codebase
834 files and 13,104 symbols in 8 modules, led by C++ (539 files) and Python (121).
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Code health
This codebase scores 5.6 out of 10 for code health, which we rate fair. It also scores maintainability 7.6 and static performance 9.9 out of 10. The three are scored separately and never blended into one number. Risk is concentrated, as it usually is: 106 of 834 files are git hotspots, and they average 2.9 — which is where the fixes pay off most.
On the leaderboards:#5 of 5 C++ repos
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1 thing worth doing this quarter.
Worth planning
Delete 1,086 unused symbols and files (16,327 lines)
Nothing in the graph reaches them, across 111 files; every reader and agent pays to skip them.
- symbols
- 1086
- lines
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- safe to delete
- Yes(inferred)
Medium effort
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Small effortReview the 67 proposed decisions
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- proposed
- 67
- accepted
- 0
Medium effort
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[](https://repowise.dev/repo/nvidia/nccl?src=badge_card)How nvidia/nccl works
Optimized primitives for collective multi-GPU communication This page is a map of the nvidia/nccl repository, written primarily in C++, rebuilt from the source each time it is indexed. Repowise parses every symbol, computes a dependency graph, scores per-file code health from complexity, duplication, test coverage and churn, mines git history for hotspots and ownership, and lifts the architectural decisions into documentation you can read here or query through MCP.
The codebase has 834 files and 13,104 symbols in 8 modules, led by C++, Python and Makefile. Code health is 5.6 out of 10, rated fair.
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