We have a web site in production that's running on W2K Server, IIS 5.0. ASP
pages talk to Oracle 8i using Oracle objects for OLE version 220.127.116.11.11.
Once we start the IIS, the web site runs fine for a while about 2 hours and
then we observed some requests don't get response. No error nothing, the
browser just keeps spinning it's wheels. When we monitor the server using
the performance monitor, we found that the counter "ASP requests queued"
keeps going up along with the "current anonymous users". The number of requests
queued never comes down as if those requests in the queue are never addressed
again. From our monitoring conclusions, nearly 1-2% of the requests are being
kept in the queue. Our customer complains that periodically their browser
stops connecting to the web site which is in sync. with what's happenning
on the server. This IIS queue has an upper limit of 3000 by default and once
it reaches that threshold, the website stops responding to ALL the requests.
We wanted to analyze these waiting requests in the queue to find out a pattern
but couldn't find any documents or tools that can do this. We actually made
multiple IIS applications within the web site to isolate the problem and
made these applications run in HIGH isolation. We found that one piece of
the web site, call it "Application X" is the problem area. If we kill this
application by killing the corresponding DLLHOST then the requests queued
comes down to zero.
One other important observation is that the browser window, once it doesn't
get response for one page in this Application X, it doesn't get response
to any other page within this Application X. All other pages on the website
that belong to other IIS applications work just fine eventhough they are
connect to the same database. Note that the page that doesn't get response
can be viewed by opening another browser window if you are not in that 1-2%
that goes into the queue. What's interesting here is that the browser window
can't open ANY of the pages of the application. We don't use ASP sessions,
We have been trying to solve this problem for about a month now and running
out of all ideas and time. Any help will be appreciated in solving this problem.
Thanks in advance
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