HF_DE_PARALLEL_MIN_FRAMES default 2000 -> 700, re-calibrated by a controlled
crossover sweep (fixed content-per-frame, three synthetic profiles x
{350..3000f} x {single,par2,par3} x 3 reps, resolved worker counts and capture
modes verified per run): par3 beats single at EVERY size in every profile —
+17-21% at 700f rising to +28-34% at 3000f. That includes a
24-sub-composition profile built specifically to reproduce the 'workers
re-pay init' failure the original 2000 floor guarded against (92k tweens,
~2.5s pollSubCompositionTimelines per worker): workers initialize
concurrently, so duplicated init costs CPU, not wall-clock, and the comp
still parallelizes +19% at 700f. Below ~700f the win thins toward +10%
while paying three hardware-GPU browsers, so a floor remains. par2 loses to
par3 in every cell of every profile — the router's existing 3-worker pin is
confirmed, not changed. Harness:
plans/drawelement-fast-capture/de-crossover-bench.sh (docs repo).
Also adds on_battery / low_power_mode to render_complete and render_error.
The DE fleet is macOS laptops, and bench sweeps on an M4 Pro caught the SAME
render flipping between ~9.6 and ~17.2 ms/frame power-management regimes
with no existing telemetry signal to segment by — the router soak reading
this change needs that dimension to interpret perf on the machines users
actually render on. Sampled per event (volatile), pmset-based, darwin-only,
null-safe on failure.
Router stays default-off behind HF_DE_PARALLEL_ROUTER; this tunes what it
will do when the soak clears it to flip.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
os.freemem() on macOS returns only truly free pages (~0.1 GB on a 24 GB
machine), ignoring inactive/purgeable/speculative pages the kernel
reclaims on demand. This caused a false "Low memory" warning on every
macOS machine.
Add getAvailableMemoryMb() that uses vm_stat on macOS and MemAvailable
from /proc/meminfo on Linux, falling back to os.freemem() elsewhere.
Also trim FFmpeg/FFprobe version strings to just "toolname X.Y.Z"
instead of the full copyright line.
