Quick answer: Vulkan pipeline cache write to disk during game shutdown taking 2+ seconds? Cache size grew; sync write blocks the main thread - write async or chunk into smaller files.
Player quits the game; window freezes for 2 seconds before closing. Disk write is the cause.
Write async on background thread
Detached thread writes the cache. Main thread continues with shutdown; OS reaps the thread.
Or write periodically during play
Periodic cache flush during low-load moments. Shutdown has less to write.
Chunk the cache
Multiple smaller cache files; write only changed chunks. Faster I/O; finer granularity.
“Disk I/O at shutdown is visible UX. Hide it.”
Audit any operation tied to game shutdown. Each adds latency to the close; players notice.