Slow file server performance, well investigated

Summary:
Windows 2003 server X64 standard edition, running on Dell Poweredge
1800, 3.6ghz Xeon with 2gb Ram.
Intel 100 s Server adapter
100 Mb link
Each workstation as 10mb link
Tested on 2000 /XP/XPX64

Issue: File downloads are faster when initiated by the file server
rather than the workstations. ie If a workstation tries to download a
file, the file will download at 50kbps.
If I log into the server and push the file onto the workstation, I get
~950 kbps, which is essentially the whole line.
I have had normal download speeds before, and nothing has been changed
configuration wise.
I have tested:
-Changing all encryption, signing, NTLM issues from secpol.msc,
including disabling all of them
-Checked that the 100mb link is detected correctly
-Ran Wireshark (formerly ethereal) and found alot of Dup Ack's when
downloading files from the workstation. Using FTP, the download speed
was fine, and hence no Dup Acks
-Updating NIC drivers, changing out NIC, switching cable
-Editing TcpAckFrequency (tried 1, 2 and 5)
-Different protocols, like FTP, which worked fine
-Another file server in a different building works fine, with the same
configuration. Also, downloads from the problem server to this server
are fine.

TODO: Run a live linux cd and test that. I just thought of that, so
I'll report that shortly.
The biggest issue for me though is why performance changes depending on
who initiates the download/upload? It must have something to do with
SMB or NTLM/LM/v2 or something that is involved in windows file
sharing, pre 2003.
Any clues?
Thanks alot

Alright, somehow the duplex was changed from full to half, upon
changing this, everything works fine.
(E-Mail Removed) wrote:
> Summary:
> Windows 2003 server X64 standard edition, running on Dell Poweredge
> 1800, 3.6ghz Xeon with 2gb Ram.
> Intel 100 s Server adapter
> 100 Mb link
> Each workstation as 10mb link
> Tested on 2000 /XP/XPX64
>
> Issue: File downloads are faster when initiated by the file server
> rather than the workstations. ie If a workstation tries to download a
> file, the file will download at 50kbps.
> If I log into the server and push the file onto the workstation, I get
> ~950 kbps, which is essentially the whole line.
> I have had normal download speeds before, and nothing has been changed
> configuration wise.
> I have tested:
> -Changing all encryption, signing, NTLM issues from secpol.msc,
> including disabling all of them
> -Checked that the 100mb link is detected correctly
> -Ran Wireshark (formerly ethereal) and found alot of Dup Ack's when
> downloading files from the workstation. Using FTP, the download speed
> was fine, and hence no Dup Acks
> -Updating NIC drivers, changing out NIC, switching cable
> -Editing TcpAckFrequency (tried 1, 2 and 5)
> -Different protocols, like FTP, which worked fine
> -Another file server in a different building works fine, with the same
> configuration. Also, downloads from the problem server to this server
> are fine.
>
> TODO: Run a live linux cd and test that. I just thought of that, so
> I'll report that shortly.
> The biggest issue for me though is why performance changes depending on
> who initiates the download/upload? It must have something to do with
> SMB or NTLM/LM/v2 or something that is involved in windows file
> sharing, pre 2003.
> Any clues?
> Thanks alot

Thank you for sharing your experience.

Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
<(E-Mail Removed)> wrote in message news:(E-Mail Removed) ups.com...
Alright, somehow the duplex was changed from full to half, upon
changing this, everything works fine.
(E-Mail Removed) wrote:
> Summary:
> Windows 2003 server X64 standard edition, running on Dell Poweredge
> 1800, 3.6ghz Xeon with 2gb Ram.
> Intel 100 s Server adapter
> 100 Mb link
> Each workstation as 10mb link
> Tested on 2000 /XP/XPX64
>
> Issue: File downloads are faster when initiated by the file server
> rather than the workstations. ie If a workstation tries to download a
> file, the file will download at 50kbps.
> If I log into the server and push the file onto the workstation, I get
> ~950 kbps, which is essentially the whole line.
> I have had normal download speeds before, and nothing has been changed
> configuration wise.
> I have tested:
> -Changing all encryption, signing, NTLM issues from secpol.msc,
> including disabling all of them
> -Checked that the 100mb link is detected correctly
> -Ran Wireshark (formerly ethereal) and found alot of Dup Ack's when
> downloading files from the workstation. Using FTP, the download speed
> was fine, and hence no Dup Acks
> -Updating NIC drivers, changing out NIC, switching cable
> -Editing TcpAckFrequency (tried 1, 2 and 5)
> -Different protocols, like FTP, which worked fine
> -Another file server in a different building works fine, with the same
> configuration. Also, downloads from the problem server to this server
> are fine.
>
> TODO: Run a live linux cd and test that. I just thought of that, so
> I'll report that shortly.
> The biggest issue for me though is why performance changes depending on
> who initiates the download/upload? It must have something to do with
> SMB or NTLM/LM/v2 or something that is involved in windows file
> sharing, pre 2003.
> Any clues?
> Thanks alot