[C2] Re: Strange problems with concurrent? access of Cocoon 2

[Stuart Roebuck <st...@adolos.co.uk>]

I've just moved over to using the latest version of Cocoon 2 and have some problems that sound related.

In the worst cases a single screen is loading up with multiple graphics missing or transposed(!).  In other words, some graphics which are just passing through Cocoon using <map:read ...> are actually being swapped round so that one graphic on the page appears where another one should.  Refreshing the page results in different graphics in different places!

I notice that tomcat is firing up two instances of Cocoon to service requests to the site, is this supposed to happen?

Here's my system setup incase it matters:

	Cocoon 2 CVS (2001-02-19)
	Tomcat 4 CVS (2001-02-19)

I've previously been running a version of Cocoon and Tomcat from about late December with no problems.

Stuart.


On Thursday, February 15, 2001, at 03:47 PM, Carsten Ziegeler wrote:

> Hello, 
>  
> since the switch from the Xalan2D07 to the Xalan-2.0.0 version in Cocoon2 we get 
> sometimes very strange problems. 
>  
> We are using frames which all four use the same stylesheets. The xalan is driven by the 
> cocoon pipeline. 
>  
> If we turn on the storing (formerly known as caching) of the TraxTransformer we get from 
> time to time a NPE in one frame. Sometimes its even worse: One frame contains part of the 
> content of another frame and the other frame is totally broken. Reloading the whole page 
> brings up all frames correctly. 
>  
> However if we turn off the storing we never did see this phenomenen. So we assume that this 
> problems have something to do with the storing. 
>  
> The store stores the Templates. Is it possible, that this problem can occure, when 
> several threads use the same Template (as delivered by the store). A thread might finish 
> first, resetting the template and the other thread still try to use it.  
>  
> This is only a guess - has someone else had these problems?  


-------------------------------------------------------------------------
Stuart Roebuck                                  stuart.roebuck@adolos.com
Lead Developer                               Java, XML, MacOS X, XP, etc.
ADOLOS                                             http://www.adolos.com/