Slower Read Speed than Write Speedfrom Unraid

[Greengiant14]

Details of System:

• Trial of Unraid 6.8.3
• 1 WD 4 TB Red Plus parity drive
• 1 WD 4 TB Red Plus data drive
• 1 WD 3tb Green data drive
• System
  • Dell XPS 435 from 2009
  • i7-920
  • 24 GB DDR 3 ram
  • Onboard Realtek gbit ethernet connection
• No VMS
• No Dockers
• Plugins
  • CA Fix Common Problems
  • Community Applications
  • Tips and Tweaks
• CAT 5e cable connecting it to a 1 gbit switch, which then uses CAT 6 cables to connect to other devices on network

 

Concern

 

I am currently getting read speeds that don't exceed 3.5 MB/s, and are typically around 2 MB/s when copying files off the array to my other computers.  I am getting write speeds to the array around 25-30MB/s (as shown in the CrystalDiskMark image attached).  From reading other posts on the forum about slow read speeds it would appear that this slow of read speeds are not typical.  I have tried suggestions that others noted as solving their read speed issues, including 

• Samba extra configuration:
  • server min protocol = SMB3_11
    client min protocol = SMB3_11
• Adjusting the Tunable (md_num_stipes): from the default of 1280 through various levels all the way to 40960
• Adjusting the Tunable (md_queue_limit): from the default 80 up to 95
• Adjusting the Tunable (md_sync_limit): from the default 5 up to 95.

 

To test if this was a hardware limitation, I booted the hardware with the old windows 10 pro boot drive I took out of the computer.  From a shared windows folder I was able to get read speeds of over 40MB/s and write speeds in the 25-30MB/s range.  This leads me to believe there is a setting in unraid, or a driver issue with one of my devices and unraid.

 

Attached diagnostics files cover the time span of a 750 MB copy of photos from the array to one of my other computers.

 

Totally new to Unraid and Linux so any assistance would be beneficial.

 

dellnas-diagnostics-20210109-1210.zip

Edited January 9, 2021 by Greengiant14
Updating system information.

[JorgeB]

That is very slow and unusual, start with a single stream iperf test to check network bandwidth.

[Greengiant14]

9 hours ago, JorgeB said:

That is very slow and unusual, start with a single stream iperf test to check network bandwidth.

So I ran iperf between my windows 10 computer and the unraid server.  Ran it twice, with unraid acting as the client in one test, and server in the other.  The results are attached.

Unraid as Client

 

Windows as Server

 

Unraid as Server

 

Windows as Client

Edited January 10, 2021 by Greengiant14
Tagging Images.

[JorgeB]

Clearly there's a LAN problem.

[will1565]

Hello, did you ever get to the bottom of this?  I have almost exactly the same issue/set up.

[Greengiant14]

Yes I managed to get it resolved.  It was an issue with the onboard NIC on the motherboard.  The dell motherboard that I am currently using has a Realtek NIC, that based on some other internet searching appears to have driver issues with Linux (at least that is what one site said).  I ended up just buying a new ASUS XG-C100C 10Gb PCI-e network card, and once installed and configured it works perfectly.  I am now getting 950+ megabit read and writes to the unraid computer where the limit in transfer speeds is now the gigabit switch.

 

While the 10Gb network card is overkill for my current needs, the difference in cost from a 1Gb, or 2.5Gb card was not that much more so I future proofed my setup.  So as mutil-gig and/or 10Gb switches become more common place at the consumer level I can upgrade my switch to reduce that bottleneck.