On Tue, Feb 25, 2003 at 09:16:36PM -0500, James Cook wrote: > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On > > Behalf Of Anders Engström > > > The idea is to make the actions "mobile" and move their place > > of execution to the EJB-container. This way you minimize the > > amount of network use - instead of letting each action look > > up resources in the EJB-tier and do RPC (== expensive network > > roundtrips), you send the actions to the EJB tier and let > > them execute in batch mode. (The same reason you use value > > objects instead of letting the web tier access entity beans directly). > > > I guess this is what I see the problem to be. Moving the Action > execution framework to the EJB-tier seems like a very bad thing to do > IMHO. Sure it eliminates some calls between tiers, but why deploy the > EJB tier and Servlet tiers to different VMs? Hasn't this been > consistently shown to be a very counter-productive model? >
My idea was not to move the entire framework to the ejb tier :) The idea was to transport just the needed information (actions, chain definition) and handle updates of the value stack on the web-tier. > Maybe you are faced with a situation where you have no control over the > server-side architecture, but it seems like moving the Actions to the > EJB-tier is a very bad thing. Well - yes and no :) We will actually be using JBoss (with an optimized stack) mostly, so your right - in this case the network round-trip/serialization is close to none. But - and this is really the reason I try to find a generic way to handle this - we may also have customers with existing app-server installations where the web-tier and ejb-tier resides on different machines. > How would the web view interact with the > ValueStack cleanly [could be passed, but man that object will grow > quickly in size], how would cookies be set, how would authentication be > preserved, what about the configuration, etc... Sure it can probably be > done, but I would benchmark the hell out of my app to determine that the > extra session bean call (or two) is the problem. It usually isn't. > Usually it is the amount of data serialized back and forth (a chain of > actions and value stack for example). :-) > Thanks to this discussion I'm pretty confident in using UserTransaction in the web-tier to handle transaction boundaries for the application. Most of our customers will be running the optimized stack of JBoss, while those who are running web/ejb-tiers on separate machines will have to put up with increased network roundtrips, or pay us to optimize the application for their needs <grin>. Best Regards //Anders -- |===================================| | Anders Engström | | [EMAIL PROTECTED] | | http://www.gnejs.net | |===================================| |Your mind is like an umbrella. | |It doesn't work unless you open it.| | /Frank Zappa | |===================================|
pgp00000.pgp
Description: PGP signature
