Avoid resolving run data for background steps#2993
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🦋 Changeset detectedLatest commit: f8f1236 The changes in this PR will be included in the next version bump. This PR includes changesets to release 16 packages
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🧪 E2E Test Results❌ Some tests failed Summary
❌ Failed Tests▲ Vercel Production (77 failed)astro (7 failed):
example (7 failed):
express (7 failed):
fastify (7 failed):
hono (7 failed):
nextjs-turbopack (7 failed):
nextjs-webpack (7 failed):
nitro (7 failed):
nuxt (7 failed):
sveltekit (7 failed):
vite (7 failed):
💻 Local Development (82 failed)astro-stable (10 failed):
express-stable (8 failed):
fastify-stable (8 failed):
hono-stable (8 failed):
nextjs-turbopack-canary (8 failed):
nextjs-turbopack-stable (8 failed):
nextjs-webpack-stable (8 failed):
nitro-stable (8 failed):
nuxt-stable (8 failed):
vite-stable (8 failed):
📦 Local Production (93 failed)astro-stable (8 failed):
express-stable (9 failed):
fastify-stable (8 failed):
hono-stable (8 failed):
nextjs-turbopack-canary (9 failed):
nextjs-turbopack-stable (9 failed):
nextjs-webpack-canary (9 failed):
nextjs-webpack-stable (9 failed):
nitro-stable (8 failed):
nuxt-stable (8 failed):
vite-stable (8 failed):
🐘 Local Postgres (88 failed)astro-stable (8 failed):
express-stable (8 failed):
fastify-stable (8 failed):
hono-stable (8 failed):
nextjs-turbopack-canary (8 failed):
nextjs-turbopack-stable (8 failed):
nextjs-webpack-canary (8 failed):
nextjs-webpack-stable (8 failed):
nitro-stable (8 failed):
nuxt-stable (8 failed):
vite-stable (8 failed):
🪟 Windows (8 failed)nextjs-turbopack (8 failed):
📋 Other (32 failed)e2e-local-dev-tanstack-start- (8 failed):
e2e-local-postgres-tanstack-start- (8 failed):
e2e-local-prod-tanstack-start- (9 failed):
e2e-vercel-prod-tanstack-start (7 failed):
Details by Category❌ ▲ Vercel Production
❌ 💻 Local Development
❌ 📦 Local Production
❌ 🐘 Local Postgres
❌ 🪟 Windows
❌ 📋 Other
✅ vercel-multi-region
❌ Some E2E test jobs failed:
Check the workflow run for details. |
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📊 Workflow Benchmarkscommit Backend:
Avg deltas compare against the most recent benchmark run on Metrics — TTFS: time to first step body (in-deployment start() → first step body, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) Scenarios — step: one trivial no-op step, no stream; no hooks, so the run stays in turbo mode (in-process fast path) · stream: one streaming step; no hooks, so the run stays in turbo mode (in-process fast path) · hook + stream: registers a hook before one step, which exits turbo mode (dispatch path) · 1020 steps: 1020 trivial sequential steps; STSO is measured between consecutive steps in the given step ranges, and WO is the whole-run overhead outside step bodies · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) 🟢/🔴 mark percentiles within/above target. Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · STSO (1-20) 20/30/60 · STSO (101-120) 30/45/90 · STSO (1001-1020) 40/60/120 All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor ( Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the |
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| workflowRun = { | ||
| ...bgRun, |
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Suggested change
| workflowRun = { | |
| ...bgRun, | |
| // `bgRun` was fetched with `resolveData: 'none'` (an | |
| // optimization for the common early-return case), so its | |
| // `input` is `undefined`. The inline replay below runs | |
| // the workflow function via `runWorkflow`, which hydrates | |
| // the workflow arguments from `workflowRun.input`. | |
| // Re-fetch the run with data resolved so replay receives | |
| // the correct arguments; otherwise a workflow that takes | |
| // input would be replayed with empty arguments, breaking | |
| // deterministic replay. | |
| const fullRun = await world.runs.get(runId, { | |
| resolveData: 'all', | |
| }); | |
| workflowRun = { | |
| ...fullRun, |
Inline-replay-after-background-step reuses a resolveData: 'none' run snapshot whose input is undefined, so workflows that take input are replayed with empty arguments, breaking deterministic replay.
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AI review: One blocking P1 finding.
| ); | ||
| workflowRun = bgRun; | ||
| workflowRun = { | ||
| ...bgRun, |
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AI review: [P1] Re-fetch the resolved run before inline replay
bgRun was loaded with resolveData: 'none', so its input is undefined. When this is the last pending background step, this object becomes workflowRun, and runWorkflow() immediately hydrates arguments from workflowRun.input; that throws Error: Invalid input and fails the workflow. The Linux/Windows unit jobs, Vitest plugin tests, and local-production Hono E2E already reproduce this path. Keep the metadata-only fetch for early-return paths, but fetch with resolveData: 'all' (and re-check terminal status) before falling through to replay.
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Summary
Why
Background-step setup only consumes run status, timing, deployment, attributes, and spec version. Resolving input and output data at this point is unnecessary, especially for fan-out workloads and runs with large inputs.
Impact
Reduces data loading and response payload size during background-step startup without changing execution semantics.
Validation
pnpm turbo run build --filter=@workflow/core...pnpm testinpackages/core— 1,483 passed, 3 expected failurespnpm typecheck