Actually Im pretty sure we could switch to STaX and use one of the annotating binder impls out there. JAXB2 or somesuch. Probably a few days of coding.
On Fri, Sep 19, 2008 at 9:01 AM, Kevin Brown <[EMAIL PROTECTED]> wrote: > On Fri, Sep 19, 2008 at 5:24 PM, Ian Boston <[EMAIL PROTECTED]> wrote: > > > Two things. > > > > Dom nearly always generates excessive object creation that under load > > stresses the GC of any JVM, I did some comparisons for smallish XML > blocks > > between DOM and SAX (< 100 elements) a while back and there was perhapse > 3x > > on speed and 4x on memory, I cant remember the precise details. I > understand > > if its node manipulation thats required Dom is just easier and may be the > > same weight, but if its xml -> object then it may be better to consider > sax > > or a push parser. Cocoon had some bad experience with dom in the request > > cycle in v1 ( al long time ago when parsers were even more creaky) > > > > Yeah, switching to sax would be a lot more efficient for the stuff that we > do, but it would also require changing a lot more code (most likely we > could > write adapters for each object type to simplify it). > > > > > > > > The other thing I have been told by IBMers is that their JVM makes it > hard > > to replace the Xerces impl. I dont know if thats relevant. > > > > The last 2 comments here http://jira.sakaiproject.org:8081/jira/ > > browse/SAK-14388 > > give some insight into a similar problem. > > > > > > HTH > > Ian > > > > On 19 Sep 2008, at 13:59, Kevin Brown wrote: > > > > I've noticed that the current performance of xml parsing is pretty bad. > >> > >> I've got a patch ready to go to improve this substantially. On our > >> internal > >> deployment it has cut down memory and CPU usage substantially and has > >> significantly improved overall response time. > >> > >> Most of the changes that need to be made are compatible with fairly old > >> xml > >> parsers, but not so many work with pooling DocumentBuilders. For > instance, > >> xerces needs to be upgraded (I'm using 2.8.1, which is about 2 years > old, > >> and that works). > >> > >> Does anyone have any strong objections to upgrading xerces, or are there > >> any > >> instances of xml parsers being used that also don't support > >> DocumentBuilder.reset ? > >> > > > > >
