if you think this is a problem on your site I would not use an xml saving of the fields because then you still have to read and parse xml - Then I would simply store the page once it is rendered in the cache if you need maximum speed.
But if a spider goes through the site the info page is for sure not the problem
. reading all directories and e.g. sort images by exif date are really hard things to do every time ...
This is why i started to store e.g. the image counter already in the cache because this speeds up the gallery a lot (e.g. a site with 200 000 images had an initial loading time of 15 sec. it's now down to 2 sec once the cache is build).
In 1.7 I most of theses caches will be added
.
The current dev build has already some - The final will have a couple more
.
/Michael