The image collector runs after every completed guest submission as well as at each flip, and
every run advanced the age it compares against. A title submits dozens of command buffers per
frame, so "unused for 16 ticks" meant a fraction of a frame: every texture sampled once a frame
was deleted and recreated, and Superliminal uploaded 3,591 textures (2.2 GB) every 5 seconds.
Deleting a GPU-written image the cache cannot read back also dropped its contents.
Only a flip now advances the age. Collection after a submission still runs, so memory pressure is
relieved during long stretches without a flip. Superliminal's per-frame uploads went from ~55 to
none, and its intro scene from 12 to 45 fps.
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