[fendale]

Ah ok - so googling a bit on this, you do specify the size when creating the namespace. So if you have multiple namespaces, they appear as separate devices on the OS, and then you can mkfs and mount each as if its a different disk. Then you get the different IO queues at the hardware level, unlike with traditional partitioning.

[tanelpoder]

Yep, exactly - with OS level partitioning or logical volumes, you'd still end up with a single underlying block device (and a single queue) at the end of the day.