Slow TCP connection from IE

I have a problem with TCP connections from controls embedded in HTML pages.

The client-application is a (.NET) usercontrol embedded in an HTML page (viewed using IE).

When the client calls:

Dim client As New System.Net.Sockets.TcpClient(_hostname, _port)

while at the same time the server calls:

i = stream.Read(bytes, 0, bytes.Length)

it takes _exactly_ 100 seconds the first time â?? subsequent calls are immediate.

It looks like itâ??s a timeout â?? but of what?!? â?? after all: I get the correct result; no problem there. Using TDImon fra SysInternals I can se that at the first (and very slow) communication, IE initially communicates at port 80 - but I havn't got a clue why. I have wondered whether it could be a DNS error, but the host I communicate to is localhost so I think that would be a rather strange reason. The problem has been verified in different organisations using several independently installed PC's.

When the client control is placed in a winform instead of in a HTML page, there is no performance problem at all.

I have a small, clean and to the point VS-solution which demonstrates the problem if anybody is interested. It consists of the control project, a winforms client, a html page and a tcp-server project.

I am sure that this is expected behaviour â?? just no for me or anyone that has looked at itâ?¦ ;^(


Regards

Henrik

Chad
Thu Feb 05 01:44:31 CST 2004

=?Utf-8?B?SGVucmlr?= <anonymous@discussions.microsoft.com> wrote in
news:776752A6-6894-485A-B67F-0B8360F523DC@microsoft.com:
> it takes _exactly_ 100 seconds the first time ? subsequent calls are
> immediate.

Are you using blocking or non blocking sockets?


--
Chad Z. Hower (a.k.a. Kudzu) - http://www.hower.org/Kudzu/
"Programming is an art form that fights back"


ELKNews - Get your free copy at http://www.atozedsoftware.com

anonymous
Sun Feb 08 19:51:05 CST 2004

I am currently using synchronous connects, writes and reads but I have tried doing it asynchronously too using the System.Net.Sockets.Socket class (after your posting) but unfortunately with the same result

If you want to try it out for yourself I have put a simple, clean and to the point zip-file at http://www.captator.dk/downloads/TcpConnection.zi

Regard

Henri

----- Chad Z. Hower aka Kudzu wrote: ----

=?Utf-8?B?SGVucmlr?= <anonymous@discussions.microsoft.com> wrote i
news:776752A6-6894-485A-B67F-0B8360F523DC@microsoft.com:
> it takes _exactly_ 100 seconds the first time â?? subsequent calls ar
> immediate.

Are you using blocking or non blocking sockets


-
Chad Z. Hower (a.k.a. Kudzu) - http://www.hower.org/Kudzu
"Programming is an art form that fights back


ELKNews - Get your free copy at http://www.atozedsoftware.co

Chad
Tue Feb 10 13:57:44 CST 2004

=?Utf-8?B?SGVucmlr?= <anonymous@discussions.microsoft.com> wrote in
news:898D1880-5AB1-4F22-AC45-AEB62C844EAC@microsoft.com:
> I am currently using synchronous connects, writes and reads but I have
> tried doing it asynchronously too using the System.Net.Sockets.Socket
> class (after your posting) but unfortunately with the same result.

I dont know - but it sounds either code or system specific.


--
Chad Z. Hower (a.k.a. Kudzu) - http://www.hower.org/Kudzu/
"Programming is an art form that fights back"


ELKNews - Get your free copy at http://www.atozedsoftware.com

William
Tue Feb 10 14:12:05 CST 2004

Not a vb guy. But I think I remember something similar testing server and
client on same box. I would narrow it down from simple things to test for
first. 1) try a sleep after the client sends its first data. This should
give the server thread a chance to get the connect. 2) try server on one
box1 and client on another box. If it works fast, then you know it has
something to do with testing on same box. You can then also use NetMon to
see what is going on (i.e. dns, connection timeouts, etc.) on the wire. hth

--
William Stacey, MVP

"Henrik" <anonymous@discussions.microsoft.com> wrote in message
news:776752A6-6894-485A-B67F-0B8360F523DC@microsoft.com...
> I have a problem with TCP connections from controls embedded in HTML
pages.
>
> The client-application is a (.NET) usercontrol embedded in an HTML page
(viewed using IE).
>
> When the client calls:
>
> Dim client As New System.Net.Sockets.TcpClient(_hostname, _port)
>
> while at the same time the server calls:
>
> i = stream.Read(bytes, 0, bytes.Length)
>
> it takes _exactly_ 100 seconds the first time - subsequent calls are
immediate.
>
> It looks like it's a timeout - but of what?!? - after all: I get the
correct result; no problem there. Using TDImon fra SysInternals I can se
that at the first (and very slow) communication, IE initially communicates
at port 80 - but I havn't got a clue why. I have wondered whether it could
be a DNS error, but the host I communicate to is localhost so I think that
would be a rather strange reason. The problem has been verified in different
organisations using several independently installed PC's.
>
> When the client control is placed in a winform instead of in a HTML page,
there is no performance problem at all.
>
> I have a small, clean and to the point VS-solution which demonstrates the
problem if anybody is interested. It consists of the control project, a
winforms client, a html page and a tcp-server project.
>
> I am sure that this is expected behaviour - just no for me or anyone that
has looked at it. ;^(
>
>
> Regards
>
> Henrik