RNTuple interface is an experimental I/O subsystem for the
ROOT analysis framework. Preliminary benchmarks have demonstrated significant performance and space improvements over the legacy
RNTuple files are split into storage and metadata. Using metadata offset information,
RNTuple files can be merged together without a costly storage decompression step. This project will implement a fast merge function to combine
RNTuple data sets. The
hadd command-line tool will be updated to take advantage of the new
RNTuple merge features.