Poor SMB Performance

My setup:

Mid-2010 12-Core 2.66 GHz Mac Pro with Gbit Ethernet
16-port Netgear Gbit Ethernet Switch
Drobo 5N Firmware 3.1.1 with 5 X 4 TB WD Se SATA III 7200 RPM 64 MB Cache drives

I’m using a too from TotuSoft to gather metrics on LAN performance:


I’m writing 1000 MB to the 5N in the tests. I ran the test multiple times (3 times for each protocol and 3 times running the copy to a Windows machine instead of the 5N) all times for each test set are within .2 bits per second or bytes per second of each other (the tool measures both). (The times are consistent for each test of the same protocol - they do not vary much at all). Times vary significantly between SMB and AFP on the Drobo and significantly with SMB on the Drobo vs SMB to a Windows box.

Copy to SMB Mount Point on 5N - 1000 MB:

Time to Complete: 490.596 seconds (Write) 33.910 seconds (Read)
Bytes per second: 2,038,334 (Write) 29,489,104 (Read)
Bits per second: 16,306,672 (Write) 235,912,832 (Read)
Mbps: 16.306 (Write) 235.912 (Read)

Copy to AFP Mount point on 5N - 1000 MB:

Time to Complete: 134.472 seconds (Write) 11.914 seconds (Read)
Bytes per second: 7,346,440 (Write) 83,928,494 (Read)
Bits per second: 59,491,520 (Write) 671,427,952 (Read)
Mbps: 59.491 (Write) 671.427 (Read)

Copy to SMB Mount Point on Windows workstation - 1000 MB:

Time to Complete: 117.423 seconds (Write) 10.470 seconds (Read)
Bytes per second: 8,516,183 (Write) 95,508,233 (Read)
Bits per second: 68,129,464 (Write) 764,065,864 (Read)
Mbps: 68.129 (Write) 764.065 (Read)

The SMB performance of the Drobo 5N seems to be really poor. Has anyone else noticed the same thing?

I see this too on my late 2012 iMac. SMB speeds are about half AFP speeds. I’d love to know what’s going on.