"XFS is often seen as the filesystem for people with massive
amounts of data. It serves that role well, Dave said, and it has
traditionally performed well for a lot of workloads. Where things
have tended to fall down is in the [benchmark plot] writing of
metadata; support for workloads that generate a lot of metadata
writes has been a longstanding weak point for the filesystem. In
short, metadata writes were slow, and did not really scale past
even a single CPU.