## Summary
Adds a `@perf` test to establish a baseline for viewport panning GC
churn on large graphs.
## Changes
- **What**: New `large graph viewport pan sweep` perf test that pans
aggressively back and forth across a 245-node graph, forcing many nodes
to cross the viewport boundary. Measures style recalcs, forced layouts,
task duration, heap delta, and DOM node count.
## Review Focus
This is **PR 1 of 2** (perf-fix-with-proof pattern). The fix (viewport
culling) will follow in a separate PR once this baseline is established
on main. CI will then show the delta proving the improvement.
The test uses 120 steps out + 120 steps back at 8px/step = ~960px total
displacement, enough to sweep across a significant portion of the large
graph layout.
┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-10479-test-add-perf-test-for-viewport-pan-sweep-GC-churn-32d6d73d365081cc9f15fe3d5890675d)
by [Unito](https://www.unito.io)
## Summary
Adds a `@perf` test that establishes a baseline for ResizeObserver
layout cost during zoom on a large graph (245 nodes).
## Changes
- **What**: New `large graph zoom interaction` perf test that zooms
in/out 30 steps on `large-graph-workflow`, measuring `layouts`,
`layoutDurationMs`, `frameDurationMs`, and `TBT`. Each zoom step
triggers ResizeObserver for all node elements due to CSS scale changes.
## Review Focus
This is **PR 1 of 2** for throttling the ResizeObserver during zoom/pan.
Once this merges and establishes a baseline on main, the fix PR (#10473)
will show a CI-proven delta demonstrating the improvement.
The test follows the same patterns as `large graph pan interaction` and
`canvas zoom sweep`.
┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-10478-test-add-large-graph-zoom-perf-test-for-ResizeObserver-baseline-32d6d73d365081169537e557c14d8c51)
by [Unito](https://www.unito.io)
## Summary
Adds Total Blocking Time (TBT) and frame duration metrics to the
performance testing infrastructure, plus three new test scenarios
covering zoom, pan, and many-nodes-idle.
## Changes
### New Metrics
- **`totalBlockingTimeMs`** — Computed from PerformanceObserver
`longtask` entries: `sum(duration - 50ms)` for tasks >50ms. Measures
main thread blocking.
- **`frameDurationMs`** — Average frame duration via rAF timing (16.67ms
= 60fps target). Measures rendering smoothness.
### New Test Scenarios
| Scenario | Description |
|---|---|
| `canvas-zoom-sweep` | 10 zoom-in + 10 zoom-out cycles on default
workflow |
| `canvas-pan-many-nodes` | 10 pan sweeps over 100-node workflow |
| `canvas-many-nodes-idle` | 2-second idle measurement with 100 nodes
rendered |
### Infrastructure
- `PerformanceHelper.ts`: Installs PerformanceObserver for longtask,
collects TBT, measures frame duration via rAF
- `perf-report.ts`: Reports TBT and frame duration in PR comment tables
- `browser_tests/assets/perf/many_nodes_100.json`: 100-node (10×10 grid)
test fixture
## Review Focus
- TBT collection clears entries at `startMeasuring()` and reads at
`stopMeasuring()` — ensure no race with observer buffering
- Frame duration sampling uses 10 frames — enough for signal without
slowing tests
Depends on: #9886, #9887
┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9910-feat-add-TBT-frameDuration-metrics-and-new-perf-test-scenarios-3236d73d365081488ae3c594a8bf7cff)
by [Unito](https://www.unito.io)
## What
Adds a 245-node workflow asset and two `@perf` tests to establish a
baseline for large-graph performance regressions (Tier 6 in the
performance backlog).
## Why
Backlog item N5: we need CI regression detection for compositor layer
management, GPU texture count, and transform pane cost at 245+ nodes.
This is PR1 of 2 — establishes baseline metrics on main. Future
optimization PRs will show improvement deltas against this baseline.
## Tests Added
- **`large graph idle rendering`** — 120 frames idle with 245 nodes,
measures style recalcs, layouts, task duration, heap delta
- **`large graph pan interaction`** — middle-click pan across 245 nodes,
stresses compositor layer management and transform recalculation
## Workflow Asset
`browser_tests/assets/large-graph-workflow.json` — 245 nodes (49
pipelines of CheckpointLoader → 2× CLIPTextEncode → KSampler +
EmptyLatentImage), 294 links. Minimal structure focused on node count.
## Verification
- [x] `pnpm typecheck:browser` passes
- [x] `pnpm lint` passes (eslint on changed file)
- [x] All link references in JSON validated programmatically
┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9940-test-add-large-graph-perf-test-with-245-node-workflow-backlog-N5-3246d73d365081f6b5d8ddb9a85e6ad0)
by [Unito](https://www.unito.io)
---------
Co-authored-by: GitHub Action <action@github.com>
## Summary
Add a permanent, non-failing performance regression detection system
using Chrome DevTools Protocol metrics, with automatic PR commenting.
## Changes
- **What**: Performance testing infrastructure — `PerformanceHelper`
fixture class using CDP `Performance.getMetrics` to collect
`RecalcStyleCount`, `LayoutCount`, `LayoutDuration`, `TaskDuration`,
`JSHeapUsedSize`. Adds `@perf` Playwright project (Chromium-only,
single-threaded, 60s timeout), 4 baseline perf tests, CI workflow with
sticky PR comment reporting, and `perf-report.js` script for generating
markdown comparison tables.
## Review Focus
- `PerformanceHelper` uses `page.context().newCDPSession(page)` — CDP is
Chromium-only, so perf metrics are not collected on Firefox. This is
intentional since CDP gives us browser-level style recalc/layout counts
that `performance.mark/measure` cannot capture.
- The CI workflow uses `continue-on-error: true` so perf tests never
block merging.
- Baseline comparison uses `dawidd6/action-download-artifact` to
download metrics from the target branch, following the same pattern as
`pr-size-report.yaml`.
## Stack
This is the foundation PR for the Firefox performance fix stack:
1. **→ This PR: perf testing infrastructure**
2. `perf/fix-cursor-cache` — cursor style caching (depends on this)
3. `perf/fix-subgraph-svg` — SVG pre-rasterization (depends on this)
4. `perf/fix-clippath-raf` — RAF batching for clip-path (depends on
this)
PRs 2-4 are independent of each other.
┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9170-feat-add-performance-testing-infrastructure-with-CDP-metrics-3116d73d3650817cb43def6f8e9917f8)
by [Unito](https://www.unito.io)
---------
Co-authored-by: GitHub Action <action@github.com>
Co-authored-by: Alexander Brown <drjkl@comfy.org>
