Anchors campaign-wide claims with measured numbers. Runs four
consumer configurations against $FIXTURE for $DURATION seconds each:
1. mpv --hwdec=vaapi (DMA-BUF zero-copy through libva)
2. mpv --hwdec=vaapi-copy (HW decode + VAImage readback)
3. firefox (iter5-amend, sandbox enabled, file:// URL)
4. mpv --hwdec=no (SW decode baseline / control)
Captures per consumer: CPU% (median + p90 from pidstat), GPU freq
median (from /sys/class/devfreq/fde60000.gpu/cur_freq, polled at
100ms cadence), drops in window (from mpv --term-status-msg),
p50 frame interval (mpv only), VmRSS delta (from /proc/PID/status).
Emits a markdown table with raw numbers per consumer — no aggregation,
no improvement ratios, no curated-benchmark framing. Honest schema
including '—' for measurements not available per consumer (e.g.
Firefox drops without internal hooks).
Phase 5 sonnet review caught 3 issues, all addressed before commit:
1. pidstat $8 column heuristic — replaced with header-driven %CPU
field detection (robust across sysstat 12.x point releases)
2. GPU freq median computation used /dev/stdin in nested subshell-
over-pipe (unreliable) — replaced with temp-file path
3. --frames=$((DURATION * 30)) hardcoded 30fps (fixture-hardcoding
per feedback_no_fixture_hardcoding.md) — replaced with
--length=$DURATION (wall-time bounded, framerate-agnostic)
Plus minor: empty cpu_pct.log now emits ERR rather than silent 0,
distinguishing measurement failure from "process used no CPU."
Reproducibility surface: run date, host, kernel, driver sha256,
fixture path+size, duration captured in the output markdown.
Hardware constants (/dev/video1, /dev/media0, devfreq path,
driver install path) are documented as PineTab2 (RK3566 via
hantro/rk3568-vpu) specific.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
claude-noether
65969da3ee