On Fri, 7 Mar 2003, Sylvain Wallez wrote: > Stephan Michels wrote: > > >On Thu, 6 Mar 2003, Stephan Michels wrote: > > > >>On Thu, 6 Mar 2003, Carsten Ziegeler wrote: > >> > >>>Stephan Michels wrote: > >>> > >>>>I do some profiling today, and wondering why the XSLT transformer > >>>>burns performance like hell in setup(). After some debugging I noticed > >>>>that the XSLT transformer create a complete new template/handler for > >>>>each call of setup(), that because the parameter 'use-store' in > >>>>cocoon.xconf is set to 'false' per default. > >>>> > >>>>After setting this parameter to 'true', the performance increased > >>>>dramatically. > >>>> > >>>>So, is there a reason, why this parameter is set to 'false'? When > >>>>not, I would change it to 'true'. > >>>> > >>>There was a reason: a memory leak :) So you can change from performance > >>>to memory leak. This leak was at least in last Xalan versions, I never > >>>tested if it is in the latest, so perhaps this is fixed now. > >>>If not, you can run into serious memory problems. > >>> > >>Doh! ;-) I'll make some longtime stability tests, to verify this. The > >>memory leak should also occur if you use the store, except if you forget > >>to remove the entries. At the moment, the concept of the XSLTC(and other) > >>doesn't make any sense, because you compile all used stylesheets for > >>every request :-/ > > > >I got NotSerializableException, if I stop the container. This remind > >with my problems with LexicalTransformer. I solved this problem > >using own writeObject() and readObject() methods, but the > >XSLTProcessorImpl using Object[] instances. I also don't know why this > >array isn't serializable, perhaps the Templates class isn't serializable. > > > >Yesterday I measured a performance enhancement by the factor 20x . > >Before each request took 2000-5000ms, which was untenable. After > >setting this option, each request took 50-100ms(cached). > > > >Perhaps you have an idea, where the problem lie on? > > > > The problem, I think, comes from the fact that XSLTProcessor uses the > transient store to store Templates, and that the <transient-store> in > cocoon.xconf has the <parameter name="use-persistent-cache" value="true"/>. > > So we actually have a transient store that persists its contents to disk !!!
This is okay, if it's only persists in dispose(). But a simple (object instanceof java.io.Serializable) due to checkSerializable() seems to be not enough to test if a object is serializable. :-/ Stephan Michels.
