Files
punktfunk/crates
enricobuehlerandClaude Fable 5 98e040fd01 fix(host/stream): the wire holds the session rate when the display outruns it
PUNKTFUNK_VDISPLAY_HZ_MULT promises extra display refreshes without one
extra frame on the wire, but the frame-driven trigger enforced its pace only
as a per-gap floor: sleep to 0.9×interval, then wake on arrival. A source
that always has a frame pending — the overdriven display under uncapped
content — settled at 0.9-interval spacing, 1.11× the negotiated rate. That
is the field report's 132 fps on a 120 fps session: ten percent more
bitrate, encode and decode for frames a 120 Hz panel can only drop.

A credit bucket (PaceBudget) now pins the long-run average at the pacing
rate: credit accrues at one frame per interval of real elapsed time, capped
at 1.25 frames of post-stall burst, and every submitted frame spends one. A
grab may run early only against banked credit, so the 0.9 floor keeps its
per-gap jitter headroom while the average cannot exceed the rate — and a
source at or below it banks faster than it spends and is never delayed.
Anchoring to real elapsed time also keeps the synchronous-encode overlap the
arrival-anchored floor bought (the owed fraction absorbs a constant encode
tail instead of stacking on top of it), and it cannot fight the phase lock's
submit grid: both agree the period is the interval.

The charge lives under the same guard as the gate — the legacy fixed tick
paces by its own grid, and charging it without ever accruing would bank
unbounded debt that stalls the loop if a rebuild later flips the capturer to
arrival-wait.

Verified on .25: native::stream tests 15/15 (three new PaceBudget tests),
punktfunk-host 369/369, clippy -D warnings clean, fmt clean.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-08-02 21:54:09 +02:00
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