I think this fundamentally goes in the wrong direction. We explicitly designed the block layer infrastructure around life time hints and not the not fish not flesh streams interface, which causes all kinds of problems. Including the one this model causes on at least some SSDs where you now statically allocate resources to a stream that is now not globally available. All for the little log with very short date lifetime that any half decent hot/cold partitioning algorithm in the SSD should be able to detect.
