Clear all

SLOW RAID 5 with Mercury Elite Pro Quad

2 Posts
2 Users
Posts: 1
New Member
Topic starter

Getting an abysmal 26 MB/s Read / 18 MB/s Write (according to BMD Disk Speed Test) on a fairly fresh Mercury Elite Pro Quad configured as RAID 5. Here's what I know:

  • 18 TB total capacity with about 7.8 TB free
  • Previously fetched upwards of 300 MB/s read/write even after half-full
  • Only about 2 months of use
  • Mostly large video assets and related project files, and I've cleaned up a bunch since it started acting slow
  • Tried different USB-C cables both directly to MacBook Pro and via my CalDigit TB3 dock
  • Running SoftRAID XT's validation now but it's estimating about 300 hours or more til complete

Any suggestions?

Posted : 21/09/2020 2:43 pm
Posts: 7566
Member Admin

You are probably using a Thunderbolt 3 cable. That would explain this.


use a USB C explicit cable and report back.

Thunderbolt 3 active cables do not support USB 3.1gen 2 if you can believe that.

Posted : 21/09/2020 9:14 pm