Confused - gigabit ethernet speed & Superhub

Blackened · 03-03-2011, 10:02

Hi all - hoping someone can help with this.

I have a PC> Superhub> Network Media Tank combo. The Superhub and NMT have gigabit ports.
I'm transferring files to the NMT over FTP at approx 100mbs (so Cute FTP tells me) - max I've hit is 134mbs.
I've been into the properties of my (onboard) ethernet and chosen 'auto-negotiation' to achieve this. There is a setting for 1000Mbps full duplex but this setting only gives me approx 50mbs speeds. Both the PC and the NMT LED's on the ports on the Superhub are green.
Am I getting full possible speed or is my onboard ethernet not gigabit and I need a gigabit PCI card?
I'm of the thinking (that with the Superhub and NMT with gigabit ports) I should be able to FTP across my network at 1000mbs and not the 100mbs I'm currently getting but I'm rubbish with numbers, seriously & the bit of Googling I did left me baffled. Would appreciate some help if poss.

Thanks.

haydnwalker · 03-03-2011, 10:06

Are you using Standard Cat5 or Cat5e cable?

AFAIK only Cat5e (or Cat 6) would support 1gbit+ LAN. Also, the max throughput you would achieve is only about 600mbps MAX (due to overheads) anyway.

MovedGoalPosts · 03-03-2011, 10:06

There can be other limitations to transfer speeds than just the network speed. In many cases the read / write speeds of hard drives will fall way below that available from gigabit networking.

Blackened · 03-03-2011, 10:08

Thanks both. 600 would be good!
Just noticed this by the way - sorry.

So I guess that answers one question.
As far as I'm aware this is standard CAT5 cable too.

haydnwalker · 03-03-2011, 10:16

Your controller is perfectly capable of gigabit, but I'm thinking its probably more a HDD r/w issue than network as Rob says

Also, the speed of processing on the S/H and your NAS box could also be bottlenecks.

If your cable is pretty new (within the last couple of years) its likely to be Cat5e

Blackened · 03-03-2011, 10:22

Cheers again Rob.
The HDD I'm using is a Western Digital WD5000AAKS - any specs I can find suggest it's R/W speed to be lower than what I'm getting anyway..

The cable I'm using is really old, and there is no writing on it to distinguish it - but the one that's running upstairs has "Gigabit CAT5e" printed on it so I'll drag that through and see if it's worth swapping them around.

512MB RAM on the NMT

qasdfdsaq · 03-03-2011, 12:49

Quote:

Originally Posted by haydnwalker

Are you using Standard Cat5 or Cat5e cable?

AFAIK only Cat5e (or Cat 6) would support 1gbit+ LAN. Also, the max throughput you would achieve is only about 600mbps MAX (due to overheads) anyway.

Cat5 cable supports gigabit speeds fine, 5e is only required if you have very poor quality cable.

In either case if it connects at gigabit it will run at gigabit, and you'll get >950mbps throughput even with overheads.

The problem is more likely a combination of latency and other bottlenecks, though most NAS devices can do about ~200-400mbps and most hard drives can do way more. The WD5000AAKS for example does around 800-900mbps.

I would suggest testing network bandwidth on it's own (i.e. isolating it from the NAS/file transfer aspect) as well as keeping an eye on latency while doing a transfer test.

Blackened · 03-03-2011, 13:26

Thanks for that. I'm not able to get to dragging the other cable through yet.

Quote:

Originally Posted by qasdfdsaq

I would suggest testing network bandwidth on it's own (i.e. isolating it from the NAS/file transfer aspect) as well as keeping an eye on latency while doing a transfer test.

Any suggestions how I would go about this?
The 'NAS' is a Popcorn Hour C-200 (so not strictly a NAS but will act as one if set up right).
I'm currently transferring files from a HDD in the PC (a WD3200AAJS) connected to the PC which is CAT5'd to the Superhub (as is the PCH).

sniper007 · 21-04-2011, 11:13

Quote:

Originally Posted by qasdfdsaq

Cat5 cable supports gigabit speeds fine, 5e is only required if you have very poor quality cable.

That's false for anyone who finds this thread in a search and in case the OP is still struggling with this issue. Make sure your cable is cat5e minimum for Gigabit speeds. You do not need cat6, but it does need to be cat5e.

Chrysalis · 28-04-2011, 00:04

overheads arent that high, I have achieved 900mbit + over the internet so it surely is possible on a lan. However for single threaded the highest I have got is about 670mbit, lan is actually slower since my internet kit was all raid, whilst at home is just single hdd's which cant keep up so about 400-500mbit here. Although it will burst higher until machine starts flushing the cache.

Ignitionnet · 29-04-2011, 23:31

A couple of points to bear in mind are that if the ethernet controller is largely software based there can be bottlenecks there, be it in terms of bus speeds, using CPU instead of on-board processing, whatever. Indeed there can be huge differences between speeds when using on-board GigE between the two points, not uncommon to find one that isn't that far away from GigE while the other port is sharing resources with other devices and doesn't do much over 100Mbps.

If you have 2 Ethernet ports try them both.

There is absolutely no requirement to use Cat5e - most Cat5 is fine for GigE. At least that's what me and IEEE standard 802.3ab - 1000BASE-T over copper wiring think. YMMV.

Sucky cable is sucky cable whether it has an e at the end or not, poor quality Cat5e just gets to suck right the way up to 350MHz.

dragon · 01-05-2011, 00:17

Quote:

Originally Posted by Blackened

Cheers again Rob.
The HDD I'm using is a Western Digital WD5000AAKS - any specs I can find suggest it's R/W speed to be lower than what I'm getting anyway..

The cable I'm using is really old, and there is no writing on it to distinguish it - but the one that's running upstairs has "Gigabit CAT5e" printed on it so I'll drag that through and see if it's worth swapping them around.

512MB RAM on the NMT

What's it's processor?
Is there anyway to find out what the cpu usage on is on the NAS/Media tank?

It could be running out of CPU horsepower and thus not be able to go any faster.

Blackened · 11-05-2011, 12:59

Cheers.
Apparently, the CPU is capable (SMP8643: 677 + 333 MHz MIPS).

The Popcorn Hour forums and it's Wiki have a list of routers/switches that are compatible with the player and can utilise it's gigabit port correctly (some really just don't ...) but there's no sign of the Superhub or the Netgear CG3101D as yet.
I've nothing set up at the moment so can't check/test any further but I do have some new CAT5e cable to install soon. Worth mentioning though for completion, the cable I was using initially is also CAT5e. A bit old and bedraggled however.

Blackened · 20-06-2011, 11:53

Just an update on this - I have just installed new Cat5e cable, so:

PC > Cat5e > Superhub > Cat5e > media player.

I'm still only achieving approx 19MB/s over the network. A 12.5GB file is taking approx 12 mins to transfer. However, some digging about suggests the media player is limited by it's CPU as suggested by Dragon.
Users on the Popcorn Hour forum that submit speeds tests for the unit @ gigabit to their Wiki, mention they are transferring at 16MB/s and submit that as 'working OK' so I can only presume that's my lot.
To sum up - yeah, everything is doing it's thing as it should be.