# Measure Startup Requests > Use when measuring what the Trilium client loads at startup — "what loads at boot?", "did this change reduce the startup bundle?", "is lazy?", or any before/after comparison for lazy-loading / code-splitting work. Drives a headless browser through login against the running dev server, records every request, and analyzes captures (summary, heavy-dependency probe, before/after diff). Don't write a new throwaway Playwright script or inline node analyzers — both already live here. - Skill: `triliumnext/measure-startup-requests` (Agent Skill, multi-file: 3 files) - Install (CLI): `npx skillmds@latest add triliumnext/measure-startup-requests` - Raw SKILL.md: https://api.skillmd.com/api/skills/triliumnext/measure-startup-requests/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: triliumnext (https://skillmd.com/u/triliumnext) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/triliumnext/measure-startup-requests --- # Measuring Trilium startup requests Two scripts in this folder do everything; don't reinvent them: ```bash # 1. Capture a full startup (login → network quiet) into a JSON file: TRILIUM_PASSWORD= node .claude/skills/measure-startup-requests/capture-requests.mjs [baseUrl] # 2. Analyze captures: node .claude/skills/measure-startup-requests/analyze-requests.mjs summary [--top N] node .claude/skills/measure-startup-requests/analyze-requests.mjs probe [name ...] node .claude/skills/measure-startup-requests/analyze-requests.mjs diff [--filter ] ``` ## Prerequisites - The dev server must already be running (`pnpm server:start`, http://localhost:8080 by default). Note which checkout it serves: the capture reflects the tree the *server* runs from, not your cwd (verify with `curl` on a file that only exists in one tree if unsure). - `TRILIUM_PASSWORD` env var if the instance has a password. **Without it the capture still "succeeds"** — it just never gets past the login page, yielding a plausible-looking ~178-request file that measures nothing. Validate every capture before drawing conclusions: a real one contains `/api/` requests (`/api/tree`, `/api/options`, ...). Zero `/api/` hits means you captured the login screen. - Playwright is resolved from `packages/trilium-e2e`; the script prefers system Edge/Chrome, so no `playwright install` is needed. ## Workflow for lazy-loading work 1. Capture a **baseline** before changing anything: `capture-requests.mjs baseline.json`. 2. Make the change (Vite dev picks it up automatically; a fresh headless session has no HMR state). 3. Capture again and compare: `analyze-requests.mjs diff baseline.json after.json`. 4. `probe` confirms specific heavy deps stayed off the boot path. ## Timing one module graph, without logging in The capture above needs a session. To weigh a *single* entry point instead — "what does reaching CKEditor actually cost?" — skip the login entirely: Vite serves module URLs unauthenticated. - URL form: `http://localhost:8080/assets/v/@fs//…/file.ts`. - Navigate a blank page to that origin, `setContent("")`, then take `performance.now()` around `await import(url).catch(() => {})`. - **The `.catch` is what makes this work.** An ES module graph is fully fetched and instantiated before any of it is evaluated, so a module whose *evaluation* throws without a session ("Logged in session not found") still yields a valid download-and-instantiate measurement. - Constructing an editor in that page needs `{ licenseKey: "GPL" }`, or `create()` throws `license-key-missing`. This is how the "first text note is slow" delay was attributed to the module graph rather than to the editor (dev server, 2026-08): `packages/ckeditor5/src/index.ts` ~290 ms / 216 modules and `EditableText.tsx` ~355 ms / 328 modules, against `PopupEditor.create()` at 83 ms first and ~25 ms after. That is why the idle preload (`preloadCommonNoteTypes` in `note_types.tsx`) is the lever — and why the 428 KB emoji `definitionsUrl` fetch is not a suspect: `EmojiRepository.init()` fires it without returning the promise, so it never blocks `create()`. ## Interpreting results - **Dev-mode numbers, not production.** The dev server serves unbundled ES modules (~500+ script requests is normal), so sizes are uncompressed and per-module. The *module sets* and import chains are what matter; production chunk sizes differ. - **Request order ≈ import discovery order.** To find what triggers a heavy load, look at the `seq` of the first module of that package and at the `/src/...` modules requested just before it, then confirm the chain by grepping for static importers. - **Sessions are stateful.** Open tabs / the active note change what loads (e.g. a text note pulls CKEditor legitimately). Totals between two captures are only comparable for the same session state; prefer the `diff` of targeted module sets, and treat full-MB totals as indicative. - **Never filter raw URLs.** Dev URLs embed the absolute checkout path via `/@fs/...`, so a worktree named e.g. `lazy-ribbon` makes every request match `/ribbon/`. The analyzer normalizes paths (strips host, `?v=`/`?t=` params, `/assets/vX.Y.Z`, and the `/@fs/` prefix) — rely on that. - Vite's hash-named shared chunks (`dist-XXXX.js`) are identified by their `.js.map` in `.cache/vite-/deps/` (each dev instance has its own): `grep -o '"[^"]*node_modules/[^"]*"' .js.map | ...` and count by package. (The 800 KB `es-toolkit`+`mdast`/`hast` chunk is CKEditor's internals, for example.) ## Reference The default `probe` list is the set of heavy deps that were deliberately made lazy (CKEditor, highlight.js, KaTeX, codemirror-vim, snapdom, force-graph, the LLM chat graph, ...) — if one of them reports `LOADED` on a plain board/empty note startup, a regression sneaked in. After the 2026-06 lazy-loading work the new-layout baseline was ~557 requests / 3.75 MB / 500 scripts (down from 810 / 8.02 MB / 745). Both eager-load offenders this file used to list have since been fixed (re-verified 2026-08): `applyModals` in `layout_commons.tsx` now wraps every dialog in `LazyDialog` (a dynamic `import()` on first summons), keeping only `PopupEditor`, `CallToAction`, `Toast` and `ShortcutHintsPanel` eager — each with a comment saying why. The Inter font is served as woff2. Don't re-report either as a finding; measure first.