Working measurement spike for Option C: aggregation runs in a server-side
DuckDB instead of shipping every row to the browser. Opt-in via
?engine=duck; the default client-side WASM path is untouched.
- routes/perspective.js: POST /perspective/init materializes a version's
forecast table into a persistent in-process DuckDB (ATTACH postgres,
so 535k rows land in ~1.5s without streaming through Node); POST
/perspective/sql executes one Perspective-generated statement, with
Arrow IPC output for viewport reads.
- ui/src/duckServerHandler.js: VirtualServerHandler that delegates SQL
generation to Perspective's own GenericSQLVirtualServerModel and POSTs
the result to the server. Adapted from @perspective-dev/client's
virtual_servers/duckdb.ts — same SQL model, different transport.
- Forecast.jsx: DUCK_MODE branch replaces the heavy /data fetch with
/perspective/init, opens the hosted table over a message port, and
shows a latency overlay. applyDepth routes through viewer.restore()
since the SQL server cannot handle view.set_depth().
Preserved for a future faster-load effort. Findings and the reason this
is not the shipped path (no interactive tree expand/collapse) are in
pf_perspective_options.md on master.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
