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[SOLVED] Less than 1 MB/s write speeds (no cache, no parity)


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I'm hoping someone has some advise for my issues with my new unraid server.  I just got the server stood up and my first task is to copy all my media off my previous nas (an ancient Dlink DNS-323).  I was able to successfully copy some files but my speeds were horrible, less than 1MB/s write speeds.


First my setup:

  • SuperMicro X10SLH-F, Bios 3.0, 2x Intel i210AT LAN ports
  • Xeon E3-1231 v3
  • 2x8GB Hynix HMT41GU7MFR8C-PB (supported)
  • 2x Toshiba 5TB 7,200 RPM  PH3500U-1I72 (1 for data, 1 for partiy).  Both drives passed preclear successfully, no SMART errors
  • 1x Samsung 250GB 850 EVO MZ-75E250B/AM (cache)
  • Consumer gigabit switch Dlink (DGS-2208)
  • Fresh install of unRAIDServer-6.0-rc3-x86_64, NerdPack is the only plugin, Trial key at this point
  • Both the unraid box and the old nas are connected with CAT6 cables to the gigabit switch.  Gigabit is recognized on both devices

My plan:

  • I didn't enable the cache drive because I knew I would be copying TB's of data, and didn't want to fill it up
  • I did enable both the parity and data drives initially.  I allowed the parity to be built before I started.
  • I used an rsync command line this:

rsync -azPh root@nas_old.home:/mnt/HD_a2/media/test/ /mnt/disk1/test/


The results:

  • Write speeds hover around 600 kB/s
  • I'm gathering that with parity enabled I should be seeing 40-50 MB/s
  • I removed the parity drive from the array leaving only the data drive and the results were the same

I've been doing a lot of reading.  I know problems like this have so many variables, everything from chipsets, LAN adapters, drivers, jumbo frames, cables, the list goes on and on.  I also know it's difficult to do apples to apples comparisons with so many different variables.  I'm no rsync expert, but that command seems pretty simple.  I guess I could connect the unraid box to the dns-323 with a crossover cable and run the command from the IPMI interface.  That would eliminate the LAN.  I did try copying an iso from my windows laptop via the SMB share and the speeds were a little better at 2.5 MB/s (measured by windows).  Eventually I'll have the cache (SSD) drive enabled so I might not feel this pain, but I want to make sure there's not something significantly wrong first.  This thread seems to have a similar issue, but that's unraid 5 and X9 rather than X10.


I'm hoping someone with a simliar setup has had simliar issues.  Anyone have any ideas?  Are there better ways for me  to copy files?  Are there better tools to measure transfer rates?  How should I continue troubleshooting?


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Try from your PC via smb and see what speeds you get there. This will rule out the dns323.  It's been a long time since I copied from my dns323 to get unRAID, but I recall seeing between 8-11 MB/s with large files.


This was using a computer on the network to initiate the copy command.


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Interesting, when I did do a copy from my windows laptop and as I mentioned, the speeds were about 2.5 MB/s.  What I didn't mention was that was via wifi.  I knew wifi would be slower, but I thought it would be better than 2.5 MB/s.  Your post prompted me to plug my laptop into the gigabit network directly.  When I started the same transfer, the speed was right around 100 MB/s!  So, you may be on to something, it may be the DNS-323.  Two questions:

  • Is 2.5 MB/s on a 54 Mbps wifi connection reasonable?
  • Is there anyting I can do to make the DNS-323 read faster?  It's RAID 1.  Can I just take a drive out and try to use it in the unraid box directly?


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Just a note.  I determined that the DNS-323 was the issue.  Since it is RAID 1 I just took out one of the drives and connected it directly to the unraid box.  I then mounted it (outside the array) and copied the data over.

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