The macOS malloc_zone_pressure_relief call (returns freed allocator pages
after raw decodes) lived in identical copies inside the desktop app and the
CLI. It now lives in lightcraft-sysmem, an isolated L0 helper crate and the
workspace's only crate allowed unsafe: one #[allow(unsafe_code)] module, a
SAFETY comment, a safe API that returns bytes released (0 off macOS), and
tests (repeat calls, release after large frees, concurrent calls). Both apps'
alloc_release.rs now just install the safe hook, and their crate roots gain
#![forbid(unsafe_code)], so every production crate except sysmem forbids it.
AGENTS.md/CLAUDE.md name the exception, per craftrules standards/never-crash.md.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- memory::budget (default min(25% RAM, 1.5 GiB); LIGHTCRAFT_MEMORY_MB, app.memoryBudget):
half for engine caches (sources + rendered previews, LRU across them via a global
use tick; the photo on screen stays), a quarter for decodes in flight (WorkGate:
thumbnails, prefetch and import probes wait; loupe/export loads never wait), an
eighth for the GPU free pool.
- GPU: best-fit buffer reuse (<= 25% slack), buffers released outside a render are
pooled at once (no stranded retired lists), pool trimmed after 3 s idle.
- Decodes drop file bytes and raw samples early, colour/crop/orient in place.
- macOS: apps install malloc_zone_pressure_relief as the release hook (after each
decode, import and idle trim): freed large blocks no longer stay resident.
14 raws + loupe + 12 steps (M4 Pro): peak RSS 1.9-2.3 GB -> 0.83-0.99 GB, footprint
2.5-2.6 GB -> 0.91-0.96 GB, heap peak 930 -> 656 MB; stepping median ~13 ms.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>