045: feedback 009's zero copy measured: ranges read where its tree keeps it instead of copied out (stored_flat, which 009 forbids): through pure_list_run 7,931 machine instructions a point, the tree's layout read directly (the descent by the guides' counts) 7,135, both above the copy's 6,136, and on them the later rungs worse (shared 1,576 against the copy's 564): a positional halving descends the tree each probe; the halving done by the tree's own order (each inner node's children by their first items' starts, read in place, then within the leaf) 6,137 and shared 578, the copy's within 2.5% (cycles 388 against 312), end to end 602 a point (2.5x Vega's C, cycles 4.1x); that needs ranges ordered by start (the data is; a keyed list's seek would say it); the list's code built into the harness for it (-O2, inlinable: exact 8,532, the runtime 40,745)

0 files changed, 0 insertions, 0 deletions