Rust · Opensource internals

DataFusion Rewrites Its Plan Trees In Place: Arc::make_mut and the End of the Clone-Collect-Rebuild Cycle

Oct 21, 2026 8 min read Jay Hubbert

DataFusion’s optimizer rewrites plan trees in place with Arc::make_mut, avoiding the clone-collect-rebuild cycle of the ownership-based TreeNode API, and skips the expensive …

Datafusion Optimizer Rust Performance Internals

How DataFusion Knows the Optimizer Has Stopped Improving: A Hash, a Node Count, and a Set of Previous Plans

Oct 21, 2026 7 min read Jay Hubbert

DataFusion’s optimizer detects that it has reached a fixed point by hashing each pass’s plan into a signature of node count plus content hash and checking a set of previous …

Datafusion Optimizer Rust Performance Internals