Daniel Friesen wrote:
I believe we
do locally (in-process) cache the preprocessor structure for
pages and templates, so multiple use of the same template won't incur as
much preprocessor work. But, the preprocessor parsing is usually one of the
fastest parts of the whole parse.
I could swear we locally cache template wikitext, and save preprocessed
data to the object cache. Least I think thats what I gathered last time
I read the code.
~Daniel Friesen (Dantman, Nadir-Seen-Fire) [
http://daniel.friesen.name]Yes
Yes. Calling a template twice will only fetch the text once, won't
increase the 'used templates' counter...
Preprocessing of wikitext over a threshold is cached serialized (it's
easier to reprocess if it's too small).
On the original question:
The tree will be reused, but it has to be expanded again. It's not clear
that you gain by using a library since you will pay the library costs on
all articles using it. Templates should be kept simple (yes, enwiki is
particularly bad at that).
In early 2007, eswiki implemented a library template
(Plantilla:Interproyecto) which was used for adding any interwikis to
sister projects. It caused server problems and got disabled by the
sysadmins.