IE Upload Performance Problem

[Keith Marchington]

This is a baffler.

Web application running on HP-UX 11.0 (B.11.00) with the whole raft of patches recommended for Java. Part of application is uploading rather large files to the application. Upload from IE 5.* and 6.* is abysmally slow. Slow like 120Kb/s over a 100BaseT network! Must be the server! But ftp to the system is running at 5Mb/s. Must be the web container. No, Opera can upload to the same web app at 8Mb/s!

So we hook up a packet sniffer. Fast uploads look just about the same as slow uploads EXCEPT that the response time to a packet with [PSH,ACK] is lots longer on the slow upload.

So is the application not responding? Let's use a different application, say one that just opens a socket and sucks bytes. Same behavior. IE is slow, Opera, Netscape are fast.

Any ideas as to why IE talking to HP-UX is behaving like this?

[Steven Sim Kok Leong]

Hi,

This is indeed interesting. Do keep us posted on any further findings. I don't have much to contribute.

Just to confirm that the issue lies with IE or perhaps an interoperability issue (however unlikely), have you tried uploading to a different webserver using IE and Netscape?

Does your packet sniffer by any chance show up any other differences apart from the slower PSH/ACK, such as TCP window sizes etc?

Hope this helps. Regards.

Steven Sim Kok Leong

[Ron Kinner]

Have you ruled out duplex mismatches? I know you found a difference between applications but your ftp rate looks pretty sorry over what should be a 100 FD network. Auto negotiate can't be trusted. For best results always nail up your speed and duplex on both ends of each segment.

Ron

[Wodisch]

Hi,

have you checked wether your IEs are using the wrong (ill-fitting) "sliding TCP window" sizes?
Read documentation about using Windows systems connected to aDSL (asynchronous Digital Subscriber Lines), as these are usually modified in that kind of environment...

HTH,
Wodisch

[Keith Marchington]

To Steven: We've done all kinds of different configs with respect to client and server.

Windows+IE to
HPUX Apache, Tomcat, HP Application Server
Windows IIS, Tomcat, Apache, HP Application Server
Linux Apache, Tomcat, HP Application Server

Windows+NS to
All of the above

Windows+Opera to
All of the above

Linux+NS to
All of the above

Linux+Opera to
All of the above

The only slow one is Windows+IE to hpux!


To Ron:

All NICs are set at full duplex. As you can see from above, all we have to do is change the browser to get different results. We use the same machines as client and server and run the browsers side-by-side and get the observed differences.


To Wodisch:

How can I tell if IE is using the "sliding TCP window sizes"? I'll gladly check to see!

Thanks for the responses.

Keith

[Ron Kinner]

Keith,

Have you tried connecting up the server to the client via a crossover cable? That would rule out any network problems. Once you do that and it doesn't change anything then I'd call Microsoft support.

Ron