[wp-hackers] Best Practices for Caching Plugin WidgetOutput?

[Jeremy Clarke]

I like to use the options route because it works no matter what and
its a pretty stable api at this point. When I played with the wp_cache
mechanism in the past I found that various things would stop it from
working (wp-config.php constant? I think that was removed), and it was
pretty confusing. The documentation was also pretty much non-existent
at that point, might be better now.

Its worth noting that the RSS aggregation/fetching system used by the
Dashboard in WP uses the options table to store  full feed content,
implying its not such a bad idea to use it for text blocks. If its
truly humonguous it might be better to avoid the IO to the db, but
since you're already fetching everything from the wp_options table it
won't be a slow/complex query at all, its only the raw size of the
result that could potentially be a problem.

In terms of updating it semi regularly I use a separate option for
each cached value that just has the timestamp of the expiry for that
value, on pageload I autoload all those expirations and update the
option if its the right time. Hooking into the relevant actions
(category update, post save) would also be a good idea if those
actions are likely to make a big difference on performance (I haven't
gotten around to it, and my users are perpetually confused about why
the new category isn't showing etc.)


-- 
Jeremy Clarke | http://simianuprising.com
Code and Design | http://globalvoicesonline.org