Calculating throughput when transferring files?

[amheck]

I have an older Simpletech NAS, and just got my HP MediaSmart server today. Both are hooked directly to the router, sitting about 2 feet from each other. I started copying my 9gb mp3 folder around 2 hours ago. Windows explorer says its got 15 minutes to go. So to round it off and be generous, if I'm transferring 9GB of data and it takes 2 hours, what sort of "speed" is that? I have to admit, I was a little surpised when I dragged and dropped the files and it said 140+ Minutes remaining.

Thanks in advance!
Aaron

 

[ChAoTiCpInOy]

9 GB = 9000 MB
2 hours = 120 minutes = 7200 seconds

9000/7200 = 1.25MBps = 1.25 megabytes per second

 

[amheck]

Nice, thanks man. Now, to put that in perspective. Is that about what I would expect, when going thru a Linksys router via a wired connection?

 

[ChAoTiCpInOy]

Ethernet Cables have usually a max thoroughput of 100Mbps = 100 megabits per second. You are getting 1.25megabytes per second, which is 10 megabits per second. So I'm not sure. That may be normal. You also have to think about the speed of the hard drives and such.

 

[spidey07]

OK - let's dispel some misinformation here.

100 Base-T ethernet = 10 MB/sec throughput. Now that's a reasonable estimate given everything else. 100 Mbs = 10 MBs thoughput. It's nowhere near exact but it's a good place to start.

If any modern hardware has a problem with 10 megabytes/sec then something is very wrong. Most likely cabling.

 

[Crusty]

Just remember that there are 8 bits in 1 byte, simple division or multiplication to go megabits <-> megabytes.

 

[spidey07]

Originally posted by: Crusty
Just remember that there are 8 bits in 1 byte, simple division or multiplication to go megabits <-> megabytes.

You can't use that with networking to determine throughput. There's a time element involved and the protocols used. Also in network world Mb = 1,000,000 bits per second. Base 10, not base 2.

 

[Crusty]

Originally posted by: spidey07

Originally posted by: Crusty
Just remember that there are 8 bits in 1 byte, simple division or multiplication to go megabits <-> megabytes.

You can't use that with networking to determine throughput. There's a time element involved and the protocols used. Also in network world Mb = 1,000,000 bits per second. Base 10, not base 2.

Blah blah it takes 10 bits to send a byte of actual data across the network sure.. but 8 bits are still in a byte

 

[JackMDS]

amheck

Unless you have an old Network component that is rated 10Mb/sec. your transfer is very Slow.

That is quite typical for the Entry Level "El Cheappo" NAS.

It is much Better to use an old computer for central Storage (even a P-II) than to buy a sub $500 NAS.

http://www.ezlan.net/net_speed.html

As an Example, My network consists on entry level Giga components, I get between my File Server (Windows Home Server) that is based on VIA C-7 (takes only 38 Watts at load) a transfer of 38 to 48 MB/sec (304 to 384 Mb/sec.)

 

[amheck]

I did consider building my own, but the cost to build (I needed everything, i.e. no parts lying around) versus the MediaSmart server at $500, well, I just couldn't build it for that cheap.

I did disable the wireless connection on my PC, and hooked up the physical cable, and the transfer from Nas#1 to the HP MSS was substantially improved. I guess the wireless link where I was running Windows Explorer to move the files from was the culpret?

 

[Crusty]

Wait a sec, so you had two explorer windows open connected to your 2 different devices and started copying from one device to the other through a computer running on a wireless connection?

 

[amheck]

Originally posted by: Crusty
Wait a sec, so you had two explorer windows open connected to your 2 different devices and started copying from one device to the other through a computer running on a wireless connection?

No, just 1 explorer window. I had both network devices mapped as a drive letter. I simple dig a drag and drop copy from the SImpleTech NAS to the HP Mediasmart server.

Like I said, both network stroage devices are connected via cable to my router. I guess I just expected that the traffic would go from 1 device to the other, i.e. in 1 router port and out the other. But apparently, the data comes back to the PC running windows explorer? That would explain why when I switched my PC to a wired connection, the x-fer was much faster, even though I didn't do a thing to the storage drives.

 

[spidey07]

Originally posted by: amheck

Originally posted by: Crusty
Wait a sec, so you had two explorer windows open connected to your 2 different devices and started copying from one device to the other through a computer running on a wireless connection?

No, just 1 explorer window. I had both network devices mapped as a drive letter. I simple dig a drag and drop copy from the SImpleTech NAS to the HP Mediasmart server.

Like I said, both network stroage devices are connected via cable to my router. I guess I just expected that the traffic would go from 1 device to the other, i.e. in 1 router port and out the other. But apparently, the data comes back to the PC running windows explorer? That would explain why when I switched my PC to a wired connection, the x-fer was much faster, even though I didn't do a think to the storage drives.

When using file sharing like that it goes to your computer, then to the other. So it's moved twice. Your 1 megabyte per second would be completely normal for wireless as at best you can get a little more than 2 megabytes/sec.