OWC Mercury Elite Pro Dual: Aggregate Read/Write Bandwidth

OWC Mercury Elite Pro Dual USB-C

MPG tested the OWC Mercury Elite Pro Dual USB-C in various configurations using two Western Digital 18TB hard drives, which are the fastest hard drives MPG has ever tested.

This page looks at aggregate bandwidth of the OWC Mercury Elite Pro Dual USB-C when multiple drives are in simultaneous use, using two Western Digital 18TB hard drives along with an OWC Elektron USB-C SSD on the rear port of the Elite Pro Dual.

CLICK TO VIEW: Recommended Storage from Large to Huge

CLICK TO VIEW: Up to 36TB Dual Drive Solution

Aggregate bandwidth

Test mule was the 2018 Mac mini connected to a dedicated Thunderbolt 3 port/bus. 10 Gbps bandwidth verified.

Simultaneous writes tested using 3 concurrent instances of disktester create-files. Simultaneous reads tested using 3 concurrent instances of disktester read-files.

This test ensures continuous maximum-speed I/O on each device.

Write performance shows that no matter the device or combination of devices, aggregate I/O bandwidth maxes-out the USB-C bus—excellent.

Read speed with a single hard drive or dual hard drives or single SSD is used is as fast as the device can go—excellent.

But when both hard drives and the SSD are in use, aggregate read bandwidth plummets to only 791 MB/sec, which is at least 228 MB/sec below the theoretical bandwidth. Why this occurs is unknown. And in most cases, it is unlikely that users would encounter this behavior since a more likely scenario is reading from some device(s) and writing to other(s).

Horizontal axis in MB/sec.

Aggregate write and read bandwidth using various devices in OWC Mercury Elite Pro Dual USB-C