The bench phase the handoff was written for is closed (splice benched,
fast-seek landed, cache removed, decision made), so the note's live half —
the firmware plumbing plan — moves into sync-commit-staging.md as "The fix —
wiring the O(depth) splice into the firmware", reconciled to the run-5 state.
The duplicated TL;DR/measurement summaries are dropped in favor of the
curve's own trail; inbound references (notes index, git_bench comments)
now point at the curve.
The real jcalixte/notes clone (570 MB pack, 1179 files) proved both index
strategies are O(N_tree) and unshippable: index.write re-hashes the tree
(611 s), and the index-free read_tree is 77 s cold and OOMs the mmap cache
(zlib crash). Record the run in the tradeoff curve, revise the verdict to an
O(depth) TreeBuilder walk, and add a handoff note with the design, firmware
call sites, and bench steps for the next session.
New docs/notes/sync-latency.md breaks down the measured ~16 s cold :sync
(Wi-Fi + SNTP + one TLS push), explains the optimistic-retry handshake saving,
the reconcile/last-writer-wins semantics, and why the rest is near the protocol
floor. Linked from the notes index, the docs index, and the Git row of the root
README.
