NV+ slow read speeds

Are you testing with large files ( > 250 MB) or small ones?

Can you try Nastester and see what it reports? http://www.808.dk/?code-csharp-nas-performance

Hi Stephen,

I was moving large files.
The results of the tester are consistent with my drag & drop results:

NAS performance tester 1.7 http://www.808.dk/?nastester
Running warmup...
Running a 400MB file write on Z: 5 times...
Iteration 1: 19.59 MB/sec
Iteration 2: 17.71 MB/sec
Iteration 3: 19.65 MB/sec
Iteration 4: 19.66 MB/sec
Iteration 5: 17.71 MB/sec
-----------------------------
Average (W): 18.86 MB/sec
-----------------------------
Running a 400MB file read on Z: 5 times...
Iteration 1: 11.22 MB/sec
Iteration 2: 11.22 MB/sec
Iteration 3: 11.71 MB/sec
Iteration 4: 11.96 MB/sec
Iteration 5: 11.99 MB/sec
-----------------------------
Average (R): 11.62 MB/sec
-----------------------------

Have you checked the SMART stats on the disks?

Also, it might be good to check for 4K alignment (and if the NAS is very old, the block size). There's info here on how to do that: http://www.rnasguide.com/2011/06/22/why ... -readynas/

Not sure what I should be looking for in the SMART stats but they're not showing any errors.
HDDs are 4K alligned and block size is 16k.

Any errors showing up in the NAS ethernet stats? Maybe copy them before and after a test.

Also, I'm not sure if this is relevant, but the Speed/Duplex mode is only giving me 100Mbit options.



This doesn't make sense though since I am able to write faster than 100Mbit.

No errors:


Auto-negotiation 0
Bad packets 0
Disconnect 0
False carrier 0
Idle errors 0
Link failures 0
Receive errors 0
Symbol errors 0
VLAN tags 0
TCP Retransmits 164
Unrecovered TCP Retransmits 1

You can specify 100 mbits to slow down gigabit if you want, but you can't uplift to 1 gigabit if the interface only negotiates 100 mbits.

Do the TCP retransmits increase during the test? They could be caused by packet loss on the PC link to the router. If so, throughput would go down.

TCP retransmits increased by 7 for a 1gb file transfer.
Another thing I just noticed from the SMART stats is that the Load Cycle on the 4th hard drive is really high. Is this normal for X-RAID?

https://imgur.com/YhIi73v

The high load cycle counts usually mean that you didn't reset the head parking threshold on the disk. It might be worth doing that, but I don't think that is causing the low read speeds.

The three command timeouts on the other disks are a bit concerning (though the counts are low, so that also isn't causing the read throughput issue).

I'd try a different ethernet cable between the PC and the router (and possible the router ethernet port while you are at it)