Gigabit Network and Vista

HEADRAT

HEADRAT

HEADRAT

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Hi,

I've got a Vista Ultimate box and 2 x MCE2005 linked up via a Gigabit network, now the transfer rates between the 2 x MCE2005 boxes are fine and if I push a file from the MCE2005 boxes to the Vista box again the transfer rate is what I expect (approx 20/30%)

Now if I try and push a file from Vista to either of the MCE2005 boxes then I get a throughput of about 6%!!

Anybody seen similar behaviour?

HEADRAT
 
kind of similar as i noticed slower transfer speeds around my gb network since using vista

i have a netgear 5port gb switch that shows green if the port is connected to a gb card and orange if it is connected to a 10/100 card

my main rig has a smc gb card in it and it appears green on the network switch. however in vista, when i check the smc card properties, the fastest speed listed is 10/100 full duplex.

when i check this after booting into xp then the top speed is 1000 full duplex

i tried reinstalling the smc driver in vista but it doesn't recognise it :(
 
Exactly the same


Pushing from my Mac and my Windows 2000 Server, it goes at about 30-35MB/sec - which is what I have always got. When I try and push from Vista to the Mac or the 2k Server box, goes at around 7MB/sec

Peculiar. Hopefully will be fixed soon
 
Apparently it may have something to do with cheap NIC's and Vista, they don't properly adhere to the standards and Vista does, basically the NIC producers cut corners that Vista now shows up :(

HEADRAT
 
This'll be due to Vista using NDIS version 6. You'll have to wait for some NDIS 6 drivers for your NIC.
 
HEADRAT said:
Apparently it may have something to do with cheap NIC's and Vista, they don't properly adhere to the standards and Vista does, basically the NIC producers cut corners that Vista now shows up :(

HEADRAT
Click to expand...


Hmmm. Well the NICs in my computer are on board an ASUS P5W DH mobo. The board is dubbed as "vista ready" - so I would assume its not a point of the hardware not being compatible. Hopefully it is just like NathanE said and its a driver issue.

I mean, i cannot be hardware since pushing TO Vista from other networked computers , achieves expected speeds. So i MUST be a driver :)
 
Once you've got some NDIS 6 drivers you'll find Gigabit throughput will be higher thanks to the new TCP stack.
 
No idea ;) What chipset is your NIC?

PS: The reason NDIS 6 is required is because all Gigabit NICs have hardware offloading facilities which is mandatory for NDIS 6 to operate the NIC at Gigabit speeds. NDIS 5 drivers work but hardware offloading provided by those drivers is no longer compatible with Vista so the NDIS driver loader explicitly disables hardware offloading when loading old drivers.
 
NathanE said:
all Gigabit NICs have hardware offloading facilities which is mandatory for NDIS 6 to operate the NIC at Gigabit speeds.
Click to expand...

Isn't that what I said ;)

HEADRAT said:
basically the NIC producers cut corners that Vista now shows up :(
Click to expand...

If your NIC isn't able to conform to NDIS6 standards then it will suck in Vista ;)

I have a onboard GigE (Nivida/Marvel) port and a PCI GigE card, none of which give great throughput!

Pretty bleak really :(

HEADRAT
 
Sorry but I meant that all Gigabit NICs do have hardware offloading features... it is just the programming interface in NDIS 6 for these features has changed quite substantially which meant that old NDIS 5 drivers are incompatible and cannot use the hardware offloading anymore.

I doubt there are any Gigabit NIC chipsets which don't support hardware offloading. Nvidia and Marvel certainly don't make such NIC chipsets.
 
So that being the case and the fact the my Linksys and Nvidia NIC's were automatically detected by the OS why do I get between 6/8% throughput?

HEADRAT
 
HEADRAT said:
So that being the case and the fact the my Linksys and Nvidia NIC's were automatically detected by the OS why do I get between 6/8% throughput?

HEADRAT
Click to expand...

He has just explained this surely? The drivers installed are only NDIS5 - which Vista doesn't work properly with. We will have to wait for the manufacturers to release NDIS6 drivers that Vista is compatible with.

That is what I am getting from what NathanE says.

NathanE, can you confirm - when I am pushing TO Vista from my Mac or Server, I get fullspeeds, is that because the Mac/Server are handling everything and Vista just recieves, where as when I try and push FROM Vista, it is Vista that is doing all the work, and cause of this NDIS5 issue, its not doing it all too well?
 
OK I see what you're saying but I have 3 different NIC's

Linksys
Marvell
Nvidia (Nforce3)

and others have posted with the latest "Vista Ready" MOBO's and are having problems so which NIC's do have NDIS6 support?

HEADRAT
 
It's the drivers that need to support NDIS 6, not the hardware. The hardware doesn't even know what NDIS is :)

"Vista Ready" stickers just mean "it works but only just and expect a few crashes" - not "it works and every driver has been optimised for Vista" :p

NathanE, can you confirm - when I am pushing TO Vista from my Mac or Server, I get fullspeeds, is that because the Mac/Server are handling everything and Vista just recieves, where as when I try and push FROM Vista, it is Vista that is doing all the work, and cause of this NDIS5 issue, its not doing it all too well?
Click to expand...
Yes receive will be fine because reception doesn't need any hardware offloading. Hardware offloading is only used for crafting the packets that are about to be sent out.

On Vista with a NDIS 5 NIC driver your CPU will be crafting all the packet headers, not your NIC, which is why Vista throttles back transmit speed to Fast Ethernet (not Gigabit) to avoid flooding the CPU with per-packet interrupts.

HEADRAT said:
So that being the case and the fact the my Linksys and Nvidia NIC's were automatically detected by the OS why do I get between 6/8% throughput?

HEADRAT
Click to expand...
The NIC drivers that Microsoft normally provide are optimised for compatibility not performance. While they are very likely to be NDIS 6 they don't implement the hardware offloading features. It would take Microsoft too much time to "reverse engineer" (and probably is illegal) how each NICs offloading instructions work.
 
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So how do we fix, we have to wait for an NDIS6 driver from our NIC manufacturer, any idea of a list of NIC's that already support NDIS6?

HEADRAT
 
I am glad I read this before setting up my gigbit switch this weekend.

One quick question, do you have to use CAT6 cable to get gigabit speeds or will decent Cat5 work?
 
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