Slow initial TCP connection to any machine.

We are affiliated with the Financial Industry, so obviously, one of
our many concerns is our network performance. We are rolling out new
HP XPPro workstations. One of our Developers noted that a code
updating tool we built was taking a total of 10-20 times longer to
update all the servers in a pool from his new machine compared to old
(Win XP vs Win2K). This tool basically does a series of file transfers
and updates several SQL servers.
To look for an explanation, he used a small utility that can send a
series of identical dummy files to another host and time how long each
one takes. With this tool, we typically see a transfer time of about
35ms for each 100k file. However, from any of the XP workstations, the
first connection/transfer takes about 1 full second, and the
subsequent ones are taking the usual 30ms - 40ms. We need to find out
why this is happening on the XP machines, because these update are now
taking a very long time to complete when multiplied by the number of
machines we have. We cannot duplicate this behavior on any of the 600+
Win2K machines we have (all of the transfers are the same).
I've tried 3 different NICs, tried every combination of settings for
the NICs (duplex, buffers, etc.). I finally set up a packet sniffer to
find out what seems to be causing the problem and it looks like that
inial connection is getting 3 TCP RSTs in a row from the target
machine in response to the incoming SYN from the XP box. Each RST is
taking about 300-400ms finish before the next SYN attempt, for a total
of 1 second (as mentioned above). Has anyone seen ANYTHING related to
this behavior? If I was to contact Microsft for technical assisance,
any hints as to how to get this escalated to the proper level with a
minimum of hassle? Thanks in advance.

Assuming the Domain Controllers are Server2000:

321169 - Slow SMB Performance When You Copy Files from Windows XP to a
Windows 2000 Domain
http://support.microsoft.com/?id=321169


--

Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com


"Aquasapien" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> We are affiliated with the Financial Industry, so obviously, one of
> our many concerns is our network performance. We are rolling out new
> HP XPPro workstations. One of our Developers noted that a code
> updating tool we built was taking a total of 10-20 times longer to
> update all the servers in a pool from his new machine compared to old
> (Win XP vs Win2K). This tool basically does a series of file transfers
> and updates several SQL servers.
> To look for an explanation, he used a small utility that can send a
> series of identical dummy files to another host and time how long each
> one takes. With this tool, we typically see a transfer time of about
> 35ms for each 100k file. However, from any of the XP workstations, the
> first connection/transfer takes about 1 full second, and the
> subsequent ones are taking the usual 30ms - 40ms. We need to find out
> why this is happening on the XP machines, because these update are now
> taking a very long time to complete when multiplied by the number of
> machines we have. We cannot duplicate this behavior on any of the 600+
> Win2K machines we have (all of the transfers are the same).
> I've tried 3 different NICs, tried every combination of settings for
> the NICs (duplex, buffers, etc.). I finally set up a packet sniffer to
> find out what seems to be causing the problem and it looks like that
> inial connection is getting 3 TCP RSTs in a row from the target
> machine in response to the incoming SYN from the XP box. Each RST is
> taking about 300-400ms finish before the next SYN attempt, for a total
> of 1 second (as mentioned above). Has anyone seen ANYTHING related to
> this behavior? If I was to contact Microsft for technical assisance,
> any hints as to how to get this escalated to the proper level with a
> minimum of hassle? Thanks in advance.

Thank you Phillip. Unfortunately, No, we are still using NT4 Domain
Controllers. (working on our AD migration plan). I guess I was
concentrating on the wrong keywords when I searched the MSKB. But,
there are several related KB articles that could prove to be a viable
solution. I will do some further testing an re-post later today.


"Phillip Windell" <@.> wrote in message news:<(E-Mail Removed)>...
> Assuming the Domain Controllers are Server2000:
>
> 321169 - Slow SMB Performance When You Copy Files from Windows XP to a
> Windows 2000 Domain
> http://support.microsoft.com/?id=321169
>
>
> --
>
> Phillip Windell [MCP, MVP, CCNA]
> www.wandtv.com
>
>
> "Aquasapien" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed) om...
> > We are affiliated with the Financial Industry, so obviously, one of
> > our many concerns is our network performance. We are rolling out new
> > HP XPPro workstations. One of our Developers noted that a code
> > updating tool we built was taking a total of 10-20 times longer to
> > update all the servers in a pool from his new machine compared to old
> > (Win XP vs Win2K). This tool basically does a series of file transfers
> > and updates several SQL servers.
> > To look for an explanation, he used a small utility that can send a
> > series of identical dummy files to another host and time how long each
> > one takes. With this tool, we typically see a transfer time of about
> > 35ms for each 100k file. However, from any of the XP workstations, the
> > first connection/transfer takes about 1 full second, and the
> > subsequent ones are taking the usual 30ms - 40ms. We need to find out
> > why this is happening on the XP machines, because these update are now
> > taking a very long time to complete when multiplied by the number of
> > machines we have. We cannot duplicate this behavior on any of the 600+
> > Win2K machines we have (all of the transfers are the same).
> > I've tried 3 different NICs, tried every combination of settings for
> > the NICs (duplex, buffers, etc.). I finally set up a packet sniffer to
> > find out what seems to be causing the problem and it looks like that
> > inial connection is getting 3 TCP RSTs in a row from the target
> > machine in response to the incoming SYN from the XP box. Each RST is
> > taking about 300-400ms finish before the next SYN attempt, for a total
> > of 1 second (as mentioned above). Has anyone seen ANYTHING related to
> > this behavior? If I was to contact Microsft for technical assisance,
> > any hints as to how to get this escalated to the proper level with a
> > minimum of hassle? Thanks in advance.