[csdvrx]

No, it doesn't, there's a hard cap. I spent a long time trying to replicate the performance I was accustomed to in XFS.

L2ARC can improves cached reads, but it's not magical, especially not for random reads... or writes. (and yes, I know about SLOG, but doing async is faster than improving sync)

And don't get me started on how ZFS is not using mirrors to improve read speed (unlike mdadm can do, cf the difference between o3 n3 f3) or how it can't take advantage of mixed arrays (ex: a fast NVME + a regular SSD or HDD to add redundancy: all the reads should go to the NVME! The writes should go async to the slow media!)

If you don't have a RAID of fast NVMe that are each given all the lanes they need, you may not see a difference.

But if you are running baremetal close to 100% of what your hardware allows, and the choice of everything you want to buy and deploy, you'll see these limits very soon.

In the end, I still chose ZFS most of the time, but there are some usecases where I think XFS over mdadm is still the best choices.