Extremely Slow IIS 6 Web Services DataSet Transmission

[William Buchanan]

We have a webservice that returns a datasets to the
client application as the return type of the webmethod.
The webservice is running on Windows Server 2003 standard
edition, IIS 6.0. The box is a pentium III Xeon with 2
gigs of RAM.

I did a little test on the test box to see how fast it
would return a dataset of about 66K records (about 6
fields in width). It took about 2 minutes, 40 secs. If
I pull the data strait from Oracle it takes less than 10
seconds.

So I went to the test box and fired up the perfmon to see
what was happening. When the request is initially made
the processor is mildly busy for about 10 secs or so and
then drops to nothing. The network outgoing is around
130KB/sec.

So I wrote the dataset to a file on the disk and just
used windows explorer to move it to another computer. It
took about 2 secs, and the network outgoing was around
9MB/sec. The file was 17MB in size. So something is
causing the IIS output to be slower.

Bandwidth throttling is not on. I tried changing the
process isolation state, disabling buffering, and
enabling HTTP compression. Nothing helped, not even a
little. Is there something that we don't have set
correctly in IIS or on the server itself?

Thanks,

William B. Buchanan
MCI
Sr. Application Developer