-* Render each changed page only once. Currently pages are rendered up to 4
- times in worst case (8 times if there's an rss feed).
-
- The issue is that rendering a page is used to gather info like the links
- on the page (and other stuff) that can effect rendering other pages. So it
- needs a multi-pass system. But rendering the whole page in each pass is
- rather obscene.
-
- It would be better to have the first pass be a data gathering pass. Such
- a pass would still need to load and parse the page contents etc, but
- wouldn't need to generate html or write anything to disk.
-
- One problem with this idea is that it could turn into 2x the work in
- cases where ikiwiki currently efficiently renders a page just once. And
- caching between the passes to avoid that wouldn't do good things to the
- memory footprint.
-
- Might be best to just do a partial first pass, getting eg, the page links
- up-to-date, and then multiple, but generally fewer, rendering passes.
-
* Don't render blog archive pages unless a page is added/removed. Just
changing a page doesn't affect the archives as they show only the title.
* Look at splitting up CGI.pm. But note that too much splitting can slow
perl down.
+
+* The backlinks code turns out to scale badly to wikis with thousands of
+ pages. The code is O(N^2)! It's called for each page, and it loops
+ through all the pages to find backlinks.
+
+ Need to find a way to calculate and cache all the backlinks in one pass,
+ which could be done in at worst O(N), and possibly less (if they're
+ stored in the index, it could be constant time). But to do this, there
+ would need to be a way to invalidate or update the cache in these
+ situations:
+
+ - A page is added. Note that this can change a backlink to point to
+ the new page instead of the page it pointed to before.
+ - A page is deleted. This can also change backlinks that pointed to that
+ page.
+ - A page is modified. Links added/removed.
sipb-www / ikiwiki.git / blobdiff