The save at exit now copies the cache only once the builds already in the driver have finished, with new ones held back meanwhile, as it already did on other drivers. Intel's driver crashed copying a cache while builds ran into it, and when the window closes the game's save is written after the pipeline cache, so a crash in that copy would lose it. The case the save at exit missed, a window closed while the boot's prewarm workers built pipelines back to back, is covered by holding new builds back: a build from the file takes about half a millisecond. The prebuild's comment keeps why its default is two threads, with the measurements of one thread for the rest of the list.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>