Function main

packages/plugin/scripts/analyze-cache-busts.ts:247–339

()

}

function main(): void {
    const opts = parseArgs(process.argv);
    if (!opts.sessionPrefix) {
        console.error(
            "usage: bun scripts/analyze-cache-busts.ts <sessionIdPrefix> [--dir <path>] [--since ISO] [--until ISO] [--limit N] [--show-diff] [--all-busts]",
        );
        process.exit(1);
    }
    const snaps = loadSnapshots(opts);
    if (snaps.length === 0) {
        console.error(`No dumps found for session prefix "${opts.sessionPrefix}" in ${opts.dir}`);
        process.exit(1);
    }
    console.log(`Session: ${snaps[0].session}`);
    console.log(`Dumps:   ${snaps.length}  (dir: ${opts.dir})`);
    console.log("");
    console.log("Dashboard times are local (UTC+2); table times are UTC.");
    console.log(
        "time(UTC)          | segs | verdict | first-divergence        | prevBytes → curBytes        | cachedPrefix@breakpoint",
    );
    console.log(
        "-------------------|------|---------|-------------------------|-----------------------------|------------------------",
    );

    // By default only BUST rows are printed so a genuine prefix bust is never
    // buried under ordinary tail-growth (STABLE) or no-op (SAME) rows. STABLE =
    // divergence is past prev's last breakpoint (pure tail addition, still a
    // cache hit). --all-rows restores the full per-request table.
    let bustCount = 0;
    for (let k = 0; k < snaps.length; k += 1) {
        const cur = snaps[k];
        if (k === 0) {
            if (opts.allRows) {
                console.log(
                    `${fmtTime(cur.createdAt)} | ${String(cur.segments.length).padStart(4)} | BASE    | (first request)         |                             |`,
                );
            }
            continue;
        }
        const prev = snaps[k - 1];
        const idx = firstDivergence(prev.segments, cur.segments);
        if (idx === -1) {
            if (opts.allRows) {
                console.log(
                    `${fmtTime(cur.createdAt)} | ${String(cur.segments.length).padStart(4)} | SAME    | (identical to prev)     |                             |`,
                );
            }
            continue;
        }
        const seg = cur.segments[idx] ?? prev.segments[idx];
        // The reusable cache was written at PREV's breakpoints. OpenCode moves the
        // tail breakpoint forward every request, so judging against CUR's final
        // breakpoint mislabels ordinary tail growth as a bust.
        const prevLastBreakpoint = lastBreakpointIndex(prev.segments);
        const verdict = idx > prevLastBreakpoint ? "STABLE" : "BUST";
        if (verdict === "BUST") bustCount += 1;
        if (verdict !== "BUST" && !opts.allRows) continue;
        const prevPrefix = cachedPrefixBytes(prev.segments, prev.segments.length);