Only 2.7 MB/sec over gigabit connection in Windows XP 64 bit ? (Skybuck's Dream PC 2006)

Hello,

I am testing Pentium III 450 mhz overclocked to 600 mhz<-> AMD X2 3800+

Windows 32 bit <-> Windows 64 bit.

The Dream PC only achieves 2.7 MB/sec when it tries to send via the
NVIDIA nForce Networking Controller.

I haven't tested the other integrated network chip yet.

This performance seems quite poor since even the PIII 600 mhz is able
to achieve 5 MB/sec or so to the AMD... with a special pci gigabit
networking card.

The question is what is causing this bottleneck ?

First I thought it could be my own software... I modified it a bit...
but I no longer think it's my software... ofcourse it could still be a
problem with my software so maybe I should test with other software as
well... but suppose I am correct and it's not the problem with my
software what else could the problem be ?

I can think of many possibilities:

1. Slow integrated network chip.
2. Windows XP 64 bit networking stack bottleneck.
3. Bad network card settings.
4. Bad windows settings/limitations/flow control (?).
5. Maybe wrong cable ? I don't think so it's a cat 0.6 cable.

The card in the PIII 450 mhz is a 3COM 3C2000-T card.

Actually the PIII computer is a very crappy computer... the pci card
could jump out any moment... it doesn't completely fit properly... but
still... it seems to work ok...

The problem seems to be with the Dream PC's hardware or software or
settings.

Has anybody else noticed poor networking performance with this software
or hardware ???

Any idea',suggestions/comments what the problem might be.. or any tips
are welcome... ?!?!?!

Bye,
Skybuck.

 

I forgot to mention one important observation:

If the packet size/payload size is only around 548 bytes the
performance is poor:
* only 2.7 MB/sec from AMD x2 3800+/xp 64 bit to PIII 600 mhz/xp 32
bit.
* only 2.8 MB/sec from PIII 600 mhz/xp 32 bit to AMD x2 3800+/xp 64
bit. However the PIII shows it can send at 8.5 MB/sec at this packet
size. So the AMD computer seems to be the bottleneck. ???

If the packet size/payload size is large for example arround 50000
bytes the performance is quite good:

* 15 MB/sec from AMD x2 3800+/xp 64 bit to PIII 600 mhz/xp 32 bit
* 20 MB/sec from PIII 600 mhz/xp 32 bit to AMD x2 3800+/xp 64 bit

Bye,
Skybuck.

 

I also tried changing some network card/chip settings... no effect.

When sending and receiving at the same time the throughput even halfs
to 1.35 MB/sec on the AMD/64 bit xp...

Not good.

Bye,
Skybuck.

 

How are the two PCs connected? If you've got a switch, does it
indicate a 1000Mb/s link? What about the Windows status display for
the network connection? Also, what's the CPU load on each box when
you're running this test? If either box is hitting 100% (or getting
close), that's going to be a limit (and a better NIC and/or driver can
help there).

If you're using a direct connection, note that this is not 100%
reliable for GigE, and that you need to use a straight-through cable
and *not* a cross over cable like you did for 10/100Mb Ethernet. If
you use a crossover cable you'll at best negotiate back to 100Mb mode.

 

Have you tested entirely using just this pair of computers ? If I were
you, I'd do some tests with more PCs. What you see as the AMD PC being
unable to send faster might very well be just the PIII receiving slower
and buffers getting saturated.

I have an AMD 3800+ X2 like yours, running win2k3 x64, and I'm pretty
sure I've hit better speeds than yours...on the internet!

 

You expect performance to go down if packet size or window size goes
down. You encounter different limits in a communications session. Raw
bit rate of the medium is just one. Another is frame rate limit of the
hosts. Another is window size, in case ACK frames are used in the
protocol.

Search under Nagle Algorithm (RFC 896) for an interesting discussion on
the latter consideration.

Bert

 

I have isolated the problem I think.

The following service is necessary for better performance:

"ForceWare Intelligent Application Manager (IAM)"

When this service is running the UDP throughput increases too:

20 MB/sec. (AMD X2 3800+ to PIII 600 mhz ) (payload size 548 bytes)
6.8 MB/sec (PIII 600 mhz to AMD X2 3800+) (payload size 548 bytes)

32 MB/sec. (AMD X2 3800+ to PIII 600 mhz ) (payload size 32000 bytes)
21 MB/sec (PIII 600 mhz to AMD X2 3800+) (payload size 50000 bytes)

That's much better ! =D

I have the following services disabled because I don't think they are
necessary and especially the apache service seems a bit dangerous:

"ForceWare IP Service"
"ForceWare user log service"
"ForceWare Web Interface" (Apache!! <- dangerous !)

Bye,
Skybuck.

 

Thanks for the response... I think I have solved all or part of the
problem... see my other posts

What is the maximum throughput you have seen at lan ?

Bye,
Skybuck

 

Hello,

Thank you too for the quick response too.

I think I have already solved the problem...

See my other thread about the solution involving a necessary NForceWare
service for better throughput... kinda strange huh ?

I will answer your questions just for kicks and some more info

They are connected via a patch through cable... so not a cross over
cable

So there is no switch...

The status is 1 gigabit connection.

AMD CPU load is 7 procent when receiving 20 MByte/sec from PIII.
(Payload size 32000 bytes)
PIII CPU load is 100 procent when sending 20 MByte/sec to AMD. (Payload
size 32000 bytes)

AMD CPU load is 30 procent when sending 33 MByte/sec from PIII.
(Payload size 32000 bytes)
PIII CPU load is 100 procent when receiving 33 MByte/sec from AMD.
(Payload size 32000 bytes)

One further note/observation is that when the AMD tries to send 40
MByte/sec and the throughput is only 33 MByte/sec the AMD CPU load is
only 20%.
That's kinda funny... so when it's sending too much the CPU load is
actually lower... kinda strange... but probably some kind of software
thingy... no biggie.

So far I think I can be quiet happy with this performance. The PIII
performance is still a bit low when the packet/payload size is around
548 bytes... Only 6.8 MB/sec or so.

Still these speeds are much better than the crappy 2.7 MB/sec...

Some day I'll also test the speed of both integrated network
controllers on the AMD... I'll simply loop the cable around and connect
them both hehe.

But for now I need the internet connection... so I am not going to do
that right now.

Though just out of curiosity... what is the fastest throughput you have
seen on a LAN/Gigabit connection ?

Bye,
Skybuck.

 

I haven't tested much on gigabit lans...with multiple simultaneous
connections I've maxed out 100mbits.

 

Hi,

I'm curious how are you doing your speed testing/measurements?

I did a lot of benchmark testing on GigE a couple of years ago. This
was with several different types of server-class machines, including
some IBM blades. Some of this was over a cross-over cable, and some via
a GigE switch (in the case of the IBM blades).

This testing was primarily "pure" network throughput, and one of the
main tools I used was "iperf":

http://dast.nlanr.net/Projects/Iperf/

This takes any disk I/O out of the equation.

Using iperf, and also with several other tools, I was able to achieve
nearly (maybe ~80-90%), but not quite, wirespeed.

Jim