Here’s the guide I use for testing disk speeds in Linux. I’m usually testing speeds on my ZFS pools.


Here’s the performance on my FreeNAS. The host hardware is a Proxmox hypervisor:

  • Dell PowerEdge R720xd
  • 2x Intel Xeon E5-2640 v2
  • 64GiB ECC RAM
  • 6x Western Digital WD Red Pro Hard Drives

The FreeNAS installation itself is virtualized with my IT mode flashed H710 HBA running in the guest as a passthrough device.

root@freenas[/mnt/red]# dd if=/dev/zero of=test bs=1G count=5 status=progress
  5368709120 bytes (5369 MB, 5120 MiB) transferred 7.494s, 716 MB/s
5+0 records in
5+0 records out
5368709120 bytes transferred in 7.493742 secs (716425679 bytes/sec)

I’m very happy with the Western Digital WD Red Pro. Just watch out to make sure you don’t buy any SMR drives.