slow file transfer

[gary]

Two computers using Windows XP Professional connected via Linksys router
using 100 base-t full duplex. When we try to transfer a file from one
computer to the other using FTP we get a transfer rate of about 30kb/sec.
Both computers claim they are connected at 100mb/sec, and the router
lights for 100 base-t are lit.
Interestingly, if we start more than one file transfer simultaneously, the
aggregate transfer rate goes up. Two files being sent simultaneously get
about 65kb/sec. four get about 200kb/sec. We’ve been unable to get much
beyond this.
I think I should be getting MUCH more. Neither computer is doing much
else, and there is no other network traffic.
What gives? Suggestions?

 

[William]

Why are you using FTP? Is there a reason? I can
transfer megabytes of data between six Win XP Pros here
at my house in nothing flat just using the Windows
Explorer.

I also use a Linksys DSL/Firewall Router and two six-port
hubs to connect all the computers through a patch-panel
in the basement. Every computer can send megabyte huge
files in rapid order to any other computer.

 

[gary]

The Windows Explorer is even slower. FTP has lower overhead. I am sure you
do get good performance, but I don't, which is the problem.

I have done additional testing.

Between two WinXP systems moves 29 kb/sec.

Reboot one machine into Linux, and FTP to Linux.
Moves much more more than a MB/sec. (More like GB/min.)

FTP to a Mac running OS/X moves about a MB/sec.

This is clearly something to do with Windows XP, not hardware, since the
same hw but with one running linux does not have the problem. I think
there are a very high number of collisions on the network with the two XP
machines up at the same time, since the overall network performance stinks
then... for instance, downloads from the internet to the Mac are slow when
XP is running.

I am going to try a different driver for the network cards.

 

[gary]

The Windows Explorer is even slower. FTP has lower overhead. I am sure you
do get good performance, but I don't, which is the problem.

I have done additional testing.

Between two WinXP systems moves 29 kb/sec.

Reboot one machine into Linux, and FTP to Linux.
Moves much more more than a MB/sec. (More like GB/min.)

FTP to a Mac running OS/X moves about a MB/sec.

This is clearly something to do with Windows XP, not hardware, since the
same hw but with one running linux does not have the problem. I think
there are a very high number of collisions on the network with the two XP
machines up at the same time, since the overall network performance stinks
then... for instance, downloads from the internet to the Mac are slow when
XP is running.

I am going to try a different driver for the network cards.

 

[gary]

Additional information:
I think it is collisions due to crummy 100 megabit handling in Win XP.
If I change one of the XP systems to 10 megabit the transfer improves from
30kilobytes/sec to about 1megabyte / sec. The performance of the Mac to
the other PC (both still running at 100 base t) improves by a factor of
about 4, and the collision lights on the switch don’t light.
So, we have a usable workaround, but it still stinks to have to downgrade
the transfer between the two PCs running XP to 10 from 100.