perf(preload): bound the extracted video frame cache - #288
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LeadcodeDev merged 1 commit intoSep 22, 2026
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Triggering scenario: a scenario JSON declaring a `video` component with `style.width/height` of 1920x1080 inside a 60 s scene at 30 fps. `.output()` (line 234) collects ffmpeg's entire rawvideo stdout into one `Vec<u8>`: 1800 frames x 8.3 MB = 15 GB. `data` then stays borrowed for the whole copy loop, so the per-frame `.to_vec()` copies build a second 15 GB structure alongside it — 30 GB peak before `output.stdout` is dropped. The result is inserted into the process-global `VIDEO_FRAME_CACHE` (assets.rs:168), which has no eviction and no `clear` function at all. There is no size, duration, or resolution cap anywhere on this path, and the inputs are entirely scenario-controlled. Under `--watch` this compounds: changing the component's `style.width` mints a new `"src:WxH"` key while the old multi-GB entry is never freed. Secondary hazard on the same line: `width * height * 4` is plain u32 arithmetic, so a declared 65536x16384 wraps to 0 and `data.len() / frame_size` panics with a divide-by-zero. Refs #220
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Sep 22, 2026
Triggering scenario: a scenario JSON declaring a `video` component with `style.width/height` of 1920x1080 inside a 60 s scene at 30 fps. `.output()` (line 234) collects ffmpeg's entire rawvideo stdout into one `Vec<u8>`: 1800 frames x 8.3 MB = 15 GB. `data` then stays borrowed for the whole copy loop, so the per-frame `.to_vec()` copies build a second 15 GB structure alongside it — 30 GB peak before `output.stdout` is dropped. The result is inserted into the process-global `VIDEO_FRAME_CACHE` (assets.rs:168), which has no eviction and no `clear` function at all. There is no size, duration, or resolution cap anywhere on this path, and the inputs are entirely scenario-controlled. Under `--watch` this compounds: changing the component's `style.width` mints a new `"src:WxH"` key while the old multi-GB entry is never freed. Secondary hazard on the same line: `width * height * 4` is plain u32 arithmetic, so a declared 65536x16384 wraps to 0 and `data.len() / frame_size` panics with a divide-by-zero. Refs #220
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Audit finding carried by this chantier. Refs #220 (RM-21).