The problem is IIS itself: IIS Session Variables are thread-locked to the
specific IIS thread on which they were instantiated.

For an example:

It is a quiet time of day, and 500 people access the IIS web server (running
ASP) and the ASP uses session objects. The session objects are stored on the
web server and are specific to the IIS thread on which they were
instantiated, and hence tie that browser (client) instance to that thread.  

Activity picks up - more load ... and as long as the Session variables are
still valid (scope / timeout and IS (not RedBack) Garbage Collection), those
original sessions (which are only runnable on the threads on which they were
instantiated) start queuing. There is spare capacity - it's just that those
Browser instances will only run on specific threads, and if those threads
are busy then you get queues.

If you destroy a Session variable - fine, but of course you would not need a
Session variable if you destroy it every time you exit an ASP page - it
would just be any other object handle.

Caution: IIS Garbage collection depends upon a number of tunables, and you
can run out of resources if you don't get everything set up right. It also
has a minimum delay inbuilt - I think this was about 20 minutes regardless.

The variables are:

ASP Queue Depth 
ASP Queue Timeout
Number of ASP Queues

The default settings varied with different IIS versions, with IIS 5 I
believe they were:

Queue Depth (don't remember)
Queue Timeout (none)
Number of ASP Queues 4

Change to suit - for openers I used 100/ 15 (secs) / 20

Hope this helps - Session Variables are the best idea I wish Microsoft had
never had (since I had to remove every one by recoding).

Regards

JayJay


-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of John Bullard
Sent: 11 June 2007 15:21
To: [email protected]
Subject: RE: [U2] RedBack Garbage Collection

>>> * Don't use session variables in IIS


Could you expand on this statement?  Do you mean don't use them to store
a copy of the RBO or not to use them in general with RedBack?
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