Measured with RawNIND on a 20.8 MP raw: an Apple M3 does a tile in 116 ms, an
RTX 3060 Ti over Tailscale 345 ms there and back; sharing blindly made the
export take 34 s instead of 6.4 s while the photo waited for the server's last
tiles. The greeting now times a check tile there and back, and tiles are
shared only when that beats this computer's own time per tile (the card's, or
the CPU's with its threads counted as `card_is_faster` does). Otherwise
`denoise.status` → `device.remote` says `slower` with both times. With the
server configured but slower the export takes 7.2 s (greeting + check tile).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
