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tos-tar-k

gigabit network fails miserably

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Test Cases.

 

Push from the Server to the Workstation (Logged on to Server)

Pull from the Server to the Worksation (Logged onto Server)

Push from the Workstation to the Server (Logged onto Workstation)

Pull from the Workstation to the Server (Logged onto Workstation)

 

Tell me what happens.

 

Then try with Xcopy.

Then try with Robocopy.

 

How much memory does the Server have, in what configuration?

 

Do you know how to use Perfmon?

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Get a copy of iperf and see what happens when you let that loose across the network. The idea here would be to prove the NIC is the issue (i.e. if it is a buffer filling up, you should still see the dropoff, if not, then I would start questioning other elements. Like the HDD)

 

http://iperf.sourceforge.net/

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VannA:

 

on pc:

 

push to server: copies at 80% of gigabit speed, dies after approx 10 seconds

pull from server: copies at 65% for about 15 seconds, then jumps up to 95% for about 3 seconds, then dies

 

on server:

 

push to PC: copies ok, at 55%

pull from PC: copies at 40% for about 20 seconds then dies

 

Get a copy of iperf and see what happens when you let that loose across the network. The idea here would be to prove the NIC is the issue (i.e. if it is a buffer filling up, you should still see the dropoff, if not, then I would start questioning other elements. Like the HDD)

i have tried changing NIC's in both computers, and it didnt help.. also, the links on that page you sent doesnt seem to work for me? Edited by tos-tar-k

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i had major issues with vistas window scaling thingy. If i was to (i forget now) do something using the interwebnetzzzz and then try to copy off the server i would see 70mb/s. If i just tried to copy id see low speeds.

 

Win7 fixed that so i gave up looking for a solution.

 

but yeah thats why i listed disabling windows vistas new tcp shindig.

 

 

**edit**

 

iperf was listed 2 posts above lol

 

look in the bin directory from memory. Needs to be run from cmd prompt.

 

one server listens one sends, used to check network performance.

Edited by B82R3S

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That link downloads the source code for that program. From there you have to compile it yourself, and then install it. Might need linux to use it

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server->pc appears to be a bit all over the shop... do you have the NICs set to gig or 100/full?

 

next step for me would be to Sniff an IPerf session at one end and see if any anomalies show up (resets, retransmissions, window adjustments etc)

 

Oh and it would be interesting to compare this TCP transfer with a UDP one (add a -u option to both client and server commands)

 

its probably what B82R3S suggested, UDP test may prove this (no window scaling applicable!)

Edited by garlic

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Massive WTF there. I notice the rate from PC to server (second image) never exceeds 100Mbps so I'd probably start looking there. Definitely looks like packet loss or out of order packets.

 

What's the network topology in that test? The two systems back to back? Or via a single switch, or multiple switches? Have you tried different cables?

 

You haven't forced link speed and duplex on any of the machines have you?

 

Are all software firewalls disabled? (including those included with your average crappy AV software like Norton SystemShagSuite 2012 or whatever it's called these days)

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try forcing tcp window sizes with iperf to see if you get better results.

I wouldn't go messing with the tests and introducing more variables at this stage.

The biggest indicator of an issue here is the huge fluctuation in transfer rate moreso than the throughput.

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ok so heres some new stuff:

i re-tested today, and got the following results (server as server, pc as client)

Posted Image

i have no idea why its faster today, have made no changes

 

when i do the -u thing, dont fully understand what that means, but it gives this:

Posted Image

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OK, /that/ (first image) looks much more sane. Don't worry about the transfer rate on the second one; It's a UDP test and defaults to 1Mbps. You need to check the stats on the RECEIVING end for the UDP test as it will show packet loss and jitter.

 

Not sure what changed the results anyway. Possibly a dodgy cable, or something changed in software?

 

What about these...

 

What's the network topology in that test? The two systems back to back? Or via a single switch, or multiple switches? Have you tried different cables?

 

You haven't forced link speed and duplex on any of the machines have you?

 

Are all software firewalls disabled? (including those included with your average crappy AV software like Norton SystemShagSuite 2012 or whatever it's called these days)

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have:

 

changed cables

changes nics in both pcs

tried with crossover cable

 

therefore it cant be nics, switch (only one in network) or cables.

have checked all firewalls, turning them off does nothing

Edited by tos-tar-k

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Don't worry about the transfer rate on the second one; It's a UDP test and defaults to 1Mbps. You need to check the stats on the RECEIVING end for the UDP test as it will show packet loss and jitter.

nothing comes up on the other end....

Edited by tos-tar-k

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bloke install win7 on a shitty hdd, and see 80mb/s from your server. End thread.

 

 

^^ thats what i did :) my server is linix tho

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Given the above, your OS, your NIC or your drivers are doing something incredibly stupid. Unless there's other software running which is stealing CPU cycles.

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bloke install win7 on a shitty hdd, and see 80mb/s from your server. End thread.

 

 

^^ thats what i did :) my server is linix tho

eh? what do you mean... i have multiple hard drives in both computers, copying fails exactly the same regardless of which used.

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