As I read that email, it seems to be saying the opposite: > We know when the underlying storage is solid state - there's a "non-rotational" field in the block

As I read that email, it seems to be saying the opposite: > We know when the underlying storage is solid state - there's a "non-rotational" field in the block device config that tells us the storage doesn't need physical seek optimisation. We should make use of that. In other words, the changes under consideration should only apply when they know they're using solid state storage. Is there information elsewhere which contradicts that? Indeed, it seems very surprising that XFS might consider removing optimizations for slower drives. It's a very popular file system in the enterprise, and anyone still storing large amounts of data is very likely to still be using rotational drives because of the massive cost difference.