Drop the static *vram-budget-mib*=22000 cap that fox flagged as wrong:
'we shouldn't limit with a max — the algo should determine how many
children based on the bend forms usage in vram.'
New algorithm:
- *gpu-total-mib* (24576 default, RTX 3090) + *gpu-headroom-mib* (1024 pad)
- *vram-per-cell-max-mib* (4096 seed) tracks largest cell observed.
- admit-fork? returns true iff
(current_vram + projected_cell + headroom) < gpu_total
- wait-admit blocks at run-loop top using projected = current per-cell
max. Self-tunes: tiny cells → many concurrent, huge cells → few.
Helper file-size-mib (stat -c %s) reads bin file size as cheap proxy
for per-cell VRAM (bin file on disk ≈ peak VRAM bend-cuda loads).
Open: cross-fork learning. record-cell-vram! runs IN THE CHILD so
parent's *vram-per-cell-max-mib* doesn't see updates without a fork-
shared signal (TODO: parent peek bin path before forking, or child
writes per-cell-size to small file the parent reads). For now the
seed value + max-tracking-in-future-runs handle the common case
where all cells are similar size.
russell@unturf.com
711095ddd8