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[stillerz]

Hi,

I just installed a brand new DNS-323 with v1.08 beta firmware and two new 1.5TB LP drives from Seagate, and I'm not seeing the performance I was hoping for in copying files from my laptop to the NAS.

I copied about 100Mb of files and saw only a 4 MB/s transfer rate as reported by the Vista file copy.  I would like that to be much higher, so I'm wondering if anyone can help with the tuning or troubleshooting of the bottleneck?

The laptop is a Dell Studio 1737 running Vista SP2.  The DNS-323 is plugged directly into the Dlink DIR-655 gigabit router, and the laptop is connected wirelessly using a 802.11n connection, that Vista reports at 130Mb/s.

I did enable jumbo frames on the DNS-323 control panel.

What else should I do?

Thanks!

[gunrunnerjohn]

Your problem is the wireless link. Although you see a raw bit rate of 130mbits, the actual througput on an 802.11x connection will rarely be half that.  In addition, the half-duplex nature of wireless connections slows down the SMB protocol used here, since there is a lot of return traffic.

Connect with a wired connnction with gigabit all around, and you should see the 15-16 mbytes/sec that the unit is capable of.

[fordem]

Another point to be aware of - file size - small file sizes affect throughput tremendously, you can achieve as much as 25~30MBytes/sec when copying multi gigabit files, using a gigabit jumbo frame connection (assuming that your PCs can accomodate it) but, as the file size drops, so does the throughput, all the way down to 0.5MBytes/sec average with files of a few megabytes.

[krenkey]

My 2 cents here, i run a wireless laptop to the dns 323 i found that when i use the vista file transfer i get horrible speeds but when i set up the ftp on the 323 my speeds went a lot higher i use the free filezilla ftp client works great. Ive also got one PC that is hard wired to the gigabit lan and the transfer speeds are approximately 18 to 19 MB/s steadily which i think is good since the PC has a small processor.

[gunrunnerjohn]

FTP will work better over wireless links, as the protocol is optimized for longer loop delays.  SMB pretty much assumes it's running on a local LAN with full duplex connections.

[fordem]

.... which i think is good since the PC has a small processor.

I think you'll find that the disk subsystems have a greater impact than the processor speed.

Just as an example I have a number of systems on hand here and two of them just happen to use very similar processors - 3.06GHz, hyperthreading Pentium IVs, both had 1GB of RAM and gigabit network interfaces - one system could consistently deliver 18~20MByte/sec throughput whilst the other would never get above 8MByte/sec.

The slower system is a desktop running Windows XPPro/sp3  with a single 80GB SATA drive and the faster system was a server running Windows Server 2003 standard edition with a pair of 250GB SATA drives in a RAID1 array.  The server has since been upgraded to 3GB of RAM, Windows Server 2008 standard edition with three 250GB drives in a RAID5 array, and throughput has dropped considerably - whilst I don't remember the exact numbers, the write speed (writing to the DNS-323) is considerably higher than the read speed (reading from the DNS-323), due to the write bottlenecking that occurs with the RAID5 array on the server.

[gunrunnerjohn]

I did a number of throughput tests when trying to sort out a Vista issue, they're posted below.

Although the processors differ, all are at least 2.4ghz dual-core machines or better, and all have 2gigs or more memory.  I have gigabit all around.


Tests from Win7 64-bit machine to Vista and XP.
----------------------
Win7 to XP      20 mbyte/sec
XP to Win7      38 mbyte/sec

Win7 to Vista   3 mbyte/sec .. Autotuning=normal
Vista to Win7   3 mbyte/sec .. Autotuning=normal

Win7 to Vista   36 mbyte/sec .. Autotuning=disabled
Vista to Win7   40 mbyte/sec .. Autotuning=disabled



Tests from Vista 32-bit to Win7 and XP.
-----------------------
Win7 to Vista   46 mbyte/sec
Vista to Win7   31 mbyte/sec

Vista to XP     20 mbyte/sec
XP to Vista     37 mbyte/sec



Tests from XP to Win7 and Vista.
-----------------------
XP from Vista   3 mbyte/sec .. Autotuning=normal
Vista from XP   3 mbyte/sec .. Autotuning=normal

XP from Vista   35 mbyte/sec .. Autotuning=disabled
Vista from XP   25 mbyte/sec .. Autotuning=disabled

XP from Win7    27 mbyte/sec
Win7 from XP    21 mbyte/sec


Tests from Win7 to D-Link DNS-323 (NAS)
---------------------------------
Win7 to DNS-323     17 mbyte/sec
Win7 from DNS-323   16 mbyte/sec

[stillerz]

Thanks for the benchmarks.  How does one disable the autotuning in Vista?

[gunrunnerjohn]

1. Open up an elevated command prompt.

2. Enter the following command to disable auto-tuning:

     netsh interface tcp set global autotuninglevel=disabled

If you decide to turn it back on again, use this command:

     netsh interface tcp set global autotuninglevel=normal

[stillerz]

Thanks, I tried disabling autotuning without any changes.  :-(

I tested with two different size copies (1) at 130Mb of smaller files and (2) at 7Gb of larger files.  The copy from Vista to DNS-323 speeds were the same with both folders.  The 130Mb transfer rate was still in the 4Mb/s range.  The 7Gb transfer peaked at about 6.5Mb/s.

I also tried copying the smaller copy (1) from the DNS-323 back to the laptop and got about 2.6Mb/s average speed.  Very bad.

Looking for any other ideas?  I will also try plugging the laptop into a wired port to see if that is the bottleneck. 

[gunrunnerjohn]

Odd, it works fine on my Vista Ultimate 32 bit machine.  I just enabled jumbo frames all around, and the Vista machine is reading and writing at around 18mbytes/sec, my Windows 7 machine is hitting 20mbytes/sec.

P.S.  You did reboot after disabling it, right?

[stillerz]

I just rebooted and tried again, but same result.

Is there something special I need to do to enable jumbo frames on Vista?

[fordem]

Search this forum for threads on speed testing - there is one in which I posted a link to a utility called NASTester, which was written specifically for the purpose of testing NAS read/write performance.

[lizzi555]

@stillerz

If you are using wireless connection, disable Jumbo Frames.
They only work in a gigabit to gigabit connection.
Wireless uses its own frame size.

In a direct connection between a desktop with gigabit LAN and the DNS I received the best result with 4K Jumbo Frames. (18-19 MB/s)
With a wireless 11N 130 MBit connection I'm limited to 6-6,5 MB/s when transfering 1 large file.
It slows down to less than 1 MB/s with thousands of small .png or .jpg files.

[gunrunnerjohn]

I had the same experience with Jumbo frames, I tried 4k and 9k, and the 4k setting works best.

As stated, wireless will not allow jumbo frames.