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[nikhalton]

I've got two Samsung HD204UI Spinpoint F4 2TB Hard Drive SATA 5400RPM 32MB Cache drives in my DNS-323.

I'm using Firmware 1.08 in the NAS. I run Windows 7 64-bit with a Samsung HD501LJ 500GB Internal SATA 16MB 7200RPM Hard Drive as my main disk. (C:\)

I have a wired network between the PC and the NAS, but this includes some Comtrend Powerline HD homeplugs, which are rated as 200Mb/s (ie about 25MB/s)

There are a couple of ethernet switches between the NAS and PC (a GetNet GS-115P 5 Port 10/100Mbps Ethernet Switch and a TP-Link 5-Port Gigabit Unmanaged Desktop Switch (TL-SG1005D) ) both of which are capable of supporting Jumbo Frames.

the full circuit between PC and NAS is:
PC-> Cat5 -> GetNet switch -> Cat5 -> Comtrend Powerline -> Electric ring main A -> Consumer unit (fusebox) -> Electric Ring main B -> Comtrend Powerline -> Cat5 -> TP-Link switch -> Cat5 -> NAS)

When transferring files from my C:\ drive to the NAS I never got data transfer above about 2.7MB/s.

When transferring files from my NAS to the C:\ drive I never got data transfer above about 4.7MB/s.

These rates apply whether I'm transferring one large file (eg 5Gb MKV), or several smaller files (2Mb MP3).

By my estimation, the slowest link in the chain is the Homeplugs which will support 25MB/s.

Is this performance in line with expectations for the kit I've described? Is there anywhere obvious that I'm losing data transfer speed? My assumption is that the homeplug network is the weak link - is that correct?

Any comments or suggestions welcome.

[dosborne]

My assumption is that the homeplug network is the weak link - is that correct?

That would be the obvious weak point. Can you temporarily remove them from the equation?

[fordem]

Powerline networking devices are susceptible to interference on the powerline - move the NAS to the other room and plug it in directly and see if there ia an improvement.

There are a couple of ethernet switches between the NAS and PC (a GetNet GS-115P 5 Port 10/100Mbps Ethernet Switch and a TP-Link 5-Port Gigabit Unmanaged Desktop Switch (TL-SG1005D) ) both of which are capable of supporting Jumbo Frames.

Either that GetNet switch is a gigabit switch (not 10/100) or it doesn't support jumbo frame - the 10/100 spec (802.3u) does not accomodate jumbo frame.

[nikhalton]

Thanks guys.

I'll try moving the NAS next to the PC and see what happens. Was planning this anyway, but it's a bit of a logistical exercise. Also, it's not a permanent solution because the Media streamer for my TV is next to where the NAS currently resides, so if it is the homeplug network, I'll have to either put up with slow transfers or no media streaming!

Thanks for pointing out the issue with the GetNet, you seem to be right. Wonder where I'd got the idea it supported jumbo frames from, because I can't find that info now! Maybe I'll swap the switches around when I move the NAS to test, so that the switch that has jumbo frame support is between the PC and NAS.

In short, though, nobody can see any reason why I shouldn't be getting better speed out of this kit, other than what's been discussed?

[Steve Pitts]

By my estimation, the slowest link in the chain is the Homeplugs which will support 25MB/s

The Getnet, being a megabit switch, is only capable of a maximum throughput of 12.5MB/s but I'd agree with others that the Powerline elements are probably providing a larger inhibitor to performance. Are you able to connect the PC into the TP-Link switch and test in that configuration temporarily?? That will give you a better idea of what the end points are capable of over a fully gigabit LAN (assuming that your PC has gigabit, you didn't say)

[nikhalton]

One other thing to mention is that I know the other links in the chain are capable of at least 6.5Mb/s because my internet connection follows the same path (through the Powerline and both switches).

This does suggest to me that there is something else affecting the performance of the DNS-323 because it's not even hitting the maximum observed speed of the local network.

[fordem]

Let's not confuse megabits/second & megabytes/second - your first post says MB/s and your most recent says Mb/s

6.5Mb/s will translate roughly to 0.65MB/s - so it seems to me that the DNS-323 is surpassing your internet based benchmark handsomely.

The other thing I'm going to tell you is this - you can sit & theorize - or - you can follow the suggestions and pickup the NAS (it weighs what 2~3lbs ?) and move it to the other end of the powerline link and establish once & for all, where the fault lies.

[lordmagneto]

Just to give another frame of reference... I have a Gigabit Router and Dlink Gigabit NICs. When I transfer files to my NAS, I get a minimal speed of 16-19 MegaBytes per/sec. I would have hoped to be faster but I will take what I can get. My systems are running Windows 7. IMHO: I think 2.5 MB/4.5MB is not as fast as it should be.