On Tue, 13 Nov 2001 10:52:17 -0500, Berin Loritsch <[EMAIL PROTECTED]> wrote:
> [EMAIL PROTECTED] wrote: > > > Hello, > > > > are there any thoughts about a parallel version of content-aggregation ? > > It would be fine to know something about the pro, cons, and future plans > > or if help is needed ;^) > > What you are refering to is a very complex beast--especially when it comes > to ordering the SAX events. For instance, let's assume we have the following > structure: > > <map:aggregate> > <map:part src="cocoon://foo.xml"/> > <map:part src="cocoon://bar.xml"/> > <map:part src="cocoon://baz.xml"/> > </map:aggregate> > > The aggregation engine would be receiving SAX events from all three > pipelines simultaneously. As a result the start and end element > tags would be intermixed. this is clearly bad. The alternative is > to cache the results of the sub pipelines until they are needed. > However, the current cache mechanism already does this! So the only > REAL benefit will be on the first access to the resource in > question. Concidering all the complexities involved, the > synchronization issues, and the overhead of threads (since we > already have to use one thread per connection); the effort involved > to buy what is in essence 10-20ms/part[2+] really isn't worth it. > In the above example, the first part doesn't save any time, but the > second two may. In essence the overall speed benefit will be > 20-40ms. Even then, I am estimating that it would be closer to only > 20ms. Especially if the second part is shorter than the first part! > > Beleive me, I thought about this in detail. I just don't see how > the benefit outweighs the costs. This is correct, except when the requests actually take longer to execute. If they actually take a lot longer, as when you're sending requests to a remote Web site, or when the processing involves complex stylesheet manipulations or what not, it makes sense to spawn multiple requests in parallel. Especially if you have a beefy machine, with lots of processors. Regards, -- Ovidiu Predescu <[EMAIL PROTECTED]> http://orion.nsr.hp.com/ (inside HP's firewall only) http://sourceforge.net/users/ovidiu/ (my SourceForge page) http://www.geocities.com/SiliconValley/Monitor/7464/ (GNU, Emacs, other stuff) --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, email: [EMAIL PROTECTED]
