SoftRaid 1+0 Volume Read Performance
I just configured a SoftRaid 1+0 volume. It uses two ThunderBay 4 chassis loaded with 4x4TB disks. The primary disks for the mirror are in the first ThunderBay, so I have chassis fault tolerance. Each ThunderBay is connected directly (no daisy chaining) to a unique Thunderbolt controller. In the 2018 Mac Mini there are four USB-C/Thunderbolt ports served by two Thunderbolt controller chips).
I tested read/write performance using BlackMagic, and get less than 500mb/s read, and ~700mb/s write. Read performance is about half what I expected, yet write is as expected.
Sure would appreciate any thoughts or debug suggestions.
Dan in VT
Try using AJA Performance Test. More reliable.
64GB file size.
I just did this test with 10TB drives in RAID 10+0, spread as you have on two enclosures.
850MB/s reads/writes on using 2 Apple 3/2 adapters on two buses.
650 writes /800 reads when daisy chaining the two enclosures.