A log without the perf trace said nothing about the free space inside the allocator's device-local blocks, which the
driver counts as in use. Every 3600 frames (600 with the perf trace) a "mem: holes" line now gives the blocks and the
allocations in them, and for the memory type the textures use most the blocks that hold a texture, the textures and
VRAM mirrors in them, the blocks at most half full, and those of them that hold nothing but textures that could be
copied elsewhere or dropped: emptying those is the most a compaction could return.
The counting is runtime/vk_tex_compact.h, which also chooses the blocks to empty, with tests/tex_compact_check.py.
A texture entry keeps the block its memory lies in, so the table is built without asking the allocator per entry.
Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
