iis 6.0 worker processes & cache object

[Param R.]

Hi all, lets assume my application is running under an app pool that has 2
worker processes servicing requests. Will the Application & Cache objects be
the same & concurrent amongst all requests? i.e. does each worker process
have its own copy of Application & Cache or do they both share them?


thanks!

 

[Scott Allen]

Yes, Param. Each application has an Application and Cache object and
they will not share them.

 

[Param R.]

You mean each Worker Process that services that application?

thanks!

 

[Scott Allen]

Inside each worker process is an application domain, appdomain for
short. In .NET the appdomain is the unit of isolation. You can't share
object's across an appdomain without doing some work. The appdomain is
a boundary.

Each ASP.NET application runs in a seperate appdomain. Each ASP.NET
application will have it's own Cache, it's own Application collection.
They won't cross appdomain boundaries. They are isolated.

 

[Param R.]

I guess that answers my question. So if I configure an application to have 2
WPs. Each WP will have 1 appdomain which will have its own copy of Cache,
Application objects etc. So if 1 request gets serviced by WP1 & changes an
application object, this will not be reflected when another request gets
services by WP2. Is that correct?

thanks!

 

[Scott Allen]

That is correct.

There can also be two appdomains inside of a single worker process,
and again they will not be changing each other's application objects.
The appdomain is the boundary, not the process.

 

[Scott Allen]

I have a little article with an overview now too:
http://odetocode.com/Articles/305.aspx

 

[Param R.]

Great article. thanks!

I have a little article with an overview now too:
http://odetocode.com/Articles/305.aspx