Severe performance problem

[Zach Russell]

I am going to take a stab that from what you described you might have script
debugging turned on. This is a great tool for using in development, however
in production you DO NOT want to be using this because it throttles the
thread back to a single thread of execution for ASP for debugging purposes.
This checkbox is under the "Home Directory" or "Virtual Directory" tab in
the MMC properties for a web site or vdir. Then select the tab "App
Debugging" and make sure that these options are not selected.

Let me know if this does not work and we can look at other options.
Something I would suggest is that you get Active Server Pages 3.0 by Wrox
Press( ISBN: 1861002610). It has an excellent chapter on tuning your IIS
server for ASP as well as writing your applications to get the maximum
performance possible.

"Oren Novotny" <Oren_N...@CryoGen.com> wrote in message
news:uaL7PCib$GA.297@cppssbbsa05...
> I am stress testing my new application and I am running into some pretty
> serious barriers. I have built a 3-tier app, roughly based on the
FMStocks
> 2000 model. Everything works, but when I run the Web Application Stress
> tool with a large number of threads & multiplier (I am testing using the
> equiv of 1000 users)
>
> My box is a Dual P3 500 w/512 megs of RAM running Win2k AS RC3 and SQL7 EE
> sp1.
>
> My middle tier are a pair of VB6 COM+ objects, which are registered as a
> Server package in COM+. When running the stress test, the CPU% doesn't go
> very high. The problem appears that ASP has only 1 executing at any given
> time. It is therefore Queuing the rest of the connections, and the
Request
> Queue is rising. The queue never has a chance to fall, it simply rises to
> the Max.
>
> Why is ASP only executing 1 concurrent page? Does it have something to do
> with the COM+ objects? None of the COM+ objects are designated as
"Requires
> Transactions". They are all set to "Uses Transactions".
>
> The site which I am testing is http://news.wonko.com. Any help would be
> most appreciated.
>
> Thanks,
> --Oren
>
>

[Mike Amundsen]

ON:

some comments on your stress testing:

sounds like you're using the WAS (HOMER) tool, right?

I see you mention a large number of threads and multiplier. What exactly
are your settings here? are you using a random dealy for the start or
hammering all threads/sockets right away?

How did you arrive at your thread/socket count for 1000 users? In real life
there will be some 'dwell time' or 'think time' for users before they
request the next page. I think the avg think time for oublic internet apps
is 5-6 seconds (longer for content based sites).

Finally, I notice you mentioned that the CPU never gets very high and that
you are seeing ASP requests queuing up. This would lead me to think that
the bottle neck is in the components or behind them in the database. ASP
can handle 10 simultaneous threads before queing a request. since you have
only one, I suspect the components are responding quite slowly.

MCA

[Mike Amundsen]

In our experience the biggest single thing you can do to improve performance
on a database app is to move the SQL to another box and leave the IIS box to
deliver ASP & COM stuff.

Once you do this, you'll be better able to pinpoint any blocking that is
occurring. Could be thw queries, could be the components. With them on two
different machines, you'll be able to PerfMon the SQL box separately to get
CPU and read/write figures.

MCA

"Oren Novotny" <o...@po.cwru.edu> wrote in message
news:OBliC95b$GA.296@cppssbbsa05...
> Thank you Mike, but Zach hit the nail on the head. I had IIS in debug
mode,
> and I did not realize that reduced IIS to only 1 thread. Upon clearing
the
> two checkboxes, IIS is now acting more normal.
>
> As for stress testing, yes I am usingWAS. I have my thread count set at
500
> with a multiplier of 2. I also set the random delat to between 0 and 100
(I
> know that is very tight).
>
> My biggest problem is due to the fact that most of my pages block, and
there
> is very little I can do to make them non-blocking, since my app is a
Weblog
> type app, and every page draws heavily from the DB (www.wonko.com is the
> current version, news.wonko.com is the Windows DNA version -- it looks the
> same, but the news.wonko.com one has the COM and all the goodies...)
>
> Now that IIS is performing normally, I need to further tune it to balance
> the load between COM+ and IIS (I only have 1 box on which to run all 3
> tiers, but I designed the app to run on 3+ boxes...)
>
> On a Dual P3-500 w/512 megs RAM and hardware RAID storage, what would be a
> reasonable number of concurrent users to aim for?
>
> Thanks,
> --Oren
>
>
> "Mike Amundsen" <mi...@amundsen.com> wrote in message
> news:esWaqoob$GA....@cppssbbsa02.microsoft.com...