Re: Overwhelming a Web Application Server

[Thorbjoern Ravn Andersen <ravn@xxxxxxxxxx>]

Nathan Andelin skrev:
> > From: Thorbjoern Ravn Andersen
> > One way to approach this, is to kill idle sessions ...
> >     
>
> Of course.  Session data and objects may be consuming a lot of memory.  And it might make sense to release it after a period of inactivity - depending on the application.  But what I was hoping that you might explain is whether that's a function of the application that the developer must code, or part of a framework, or some sort of configuration setting in an application server?  An optional setting for each application, or JSP, or Servlet, or Session Manager, or whatever?
>
>   
> > Another approach used AFAIK in Apache Tomcat and other
> > Java web servers is to persist the oldest sessions to disk ...
> >     
>
> And the same questions apply here.  Code that into the application?  Use a framework?  A configuration setting in Tomcat?  Does serializing an object automatically release memory?
>   
For Java Web Servers they usually implement some version of the Java 
Servlet specification, where this is handled by the optional 
<session-timeout> tag in web.xml

See http://edocs.bea.com/wls/docs61/webapp/web_xml.html#1017356

You can programmatically invalidate a session from within your web 
application.

I really like the very sharp divide between INSIDE a web application, 
and OUTSIDE.  It allows you to reuse correctly written web-applications 
easily between containers.