The perf lines could not see pacing. In the 0.10.0 fresh session (nx2navi.1.log, 7,974,927 bytes) all 666 windows read
"pacing 0%" and "bound: cpu" and all 70 slow-frame lines "pacing 0.0 drain 0.0", while 610 windows had a 16.x ms
interval at fps_limit 60 under the game's own limiter. The pacer's wait happened where perf does not count it:
vk_backend.c present_image's wait for the present thread to take the previous picture was untimed, perf_end drops
waits on any thread but the presenting and replay ones (a game may acquire its window image on another), and the
acquire's GPU wait was counted twice, as pacing around b->fence_wait and as a fence wait inside vk_sync_fence_wait
(F-7-04).
- host.h: PERF_HANDOFF, the presenting thread's wait to hand the present thread the next picture, timed in
present_image from under pl (where pending is read) and kept in PresentJob.handoff_ns. perf_end_any counts a wait
on any other guest thread into a sum that perf_present adds to the frame before ft_frame reads its parts.
- nvn_api_obj.c nvnWindowAcquireTexture: the pacer's sleep is timed with perf_end_any; the GPU wait counts only as
the fence wait it is; one line names the threads that acquire and present once the first present is known.
- vk_backend.c present_main: the TRACE=present line adds the present call's time (vkQueuePresentKHR, under the queue
lock, where an overlay's frame limiter sleeps) and the job's hand-off wait; with trace=perf, a line per 60 presents
gives the present thread's blit and submit, paced wait, present call (avg, max), time past target and the hand-off.
- perf.c: "handoff" in the window line's shares and the slow-frame line, "hand-off" in the worst-frame lines and as a
cause of its own for frames over 25 ms and the stutter map. The "bound:" rule stays as it is until play-test numbers
exist.
- The cause list changes together: perf.c FT_C_* and ft_cause_name, stutter_map.c SM_CAUSES and cause_short,
tests/stutter_hitch_check.c names[] (now sized from SM_CAUSES), and tools/stutter_map.py, whose cause and hitch
patterns now take a hyphen. flight.c's frames.tsv gets a handoff_ms column (blocked_names checked against PERF_N),
and tools/flight_view.py lists it.
- tools/perf_summary.py reads the hand-off share, the present-thread lines and the TRACE=present lines, and prints
percentiles of the present interval, paced wait, time past target, present call and hand-off.
New tests/perf_summary_check.py makes lines with the runtime's format strings (checked against the C sources) and
checks the percentiles, the window averages and the hand-off share, and that older lines without these fields still
parse; tests/stutter_map_check.py gets a hand-off hitch and area cause, which the old patterns dropped. Diagnostics
only: no wait, pacing or presentation change. Not reproduced before the change (it needs a game run with trace=perf).
perf_summary_check, stutter_map_check, stutter_hitch_check, flight_flash_check and frame_step_check pass; every
runtime file compiles with the dev flags after the host.h change, and the changed files add no -Wall -Wextra warnings.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
In the 2026-11-13 session three frames of 87, 91 and 96 ms after an area load each counted as a change of pace, as each was followed by one as long, and loads that only the texture pool saw (no area file read, so no scene line) were charged to play. Consecutive long frames are now one episode, counted once with their summed time, its line giving that time and the first frame's parts; a run of more than 8 long frames none of which stands out is still a change of pace. The texture pool's start and end of an area load mark an area load for the map, as the game's own loads do.
With trace = perf, the slow write-watch queries and freezes past the 200 lines they may log are counted and given every 60 frames, so a late area load still shows them; the session's lines had run out by frame 36,387.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>