large number of context switches & pagefaults

[Guest_imported]

i have build a com+ application for a website (vb 6.0 , STA, ActiveX DLLs).

it works with several user classes wich use a so called payload class to make XML strings and converting them with XSL to HTML, sending them back to the asp page for output.

now, when i started stressing the application and it comes to around 150 concurrent users pagefaults increase to about 5-6000 per second and there are around 40000 context switches per second ==> webserver is at 100%

i'm using CreateInstance for accessing the payload object from inside the user classes and the NEW keyword for ADODB stuff and MSXML (4.0).

is there some basic error in this concept or has anyone of you experienced similar behavior of an application (all dlls are registered in the com+ service manager) and most important: where is the root of this problem?

if anyone of you has some hints for me i'd be more than grateful, cause i've not discovered the bottleneck yet.

thanks in advanced,

thomas kay

P.S.: frequently visited pages are cached in application variables to free database resources (database and webserver are on two different servers, using MS win2k advanced server and SQL server 6.0)

 

[DASMAN]

Is your web server a Multiple Processor System?


DAS

 

[Guest_imported]

yup 2 times 1Ghz pIII
1gig ram

 

[DASMAN]

Ok,
I experience a similar problem with a dual processor system using just com+ components, no asp.
My application it's working faster in a single processor than on a dual processor. Try setting process affinity to the dllhost to just one processor an see what happend.
I still can't fix it.

DAS

 

[Guest_imported]

sorry for the delay, everything works fine now, left out a parameter for an applet and this darn thing called the index page 20 times per second )

now everything is fine and smooth at 10-15% cpu usage with 1000 concurrent users caching xml rules!