[wp-hackers] RE: apache 2.2.2 upgrade

[David Chait]

WP2's 'object cache' should be disabled on anything except a dedicated 
server, along with one of the memory cache drop-ins and not the base system. 
And, you should be an intermediate to expert WAMP admin type..

Otherwise, it has been shown to be of negligible performance difference, the 
root of a number of security issues, possibly the root of some memory 
issues, and the cause of many wacky headaches for new users.

WP-Cache otoh is a descendant of "Staticize", a hack for WP1 that captures 
page results as PHP, ALMOST getting to 'static pages'... but not quite since 
it still has to load and run some PHP code to get there.  With a PHP opcode 
cache, and a well tuned system, I'd expect it to run pretty darn fast -- not 
quite raw HTML, but more than fast enough for slashdottings.  It could be 
further modified for sites that are primarily static to cache to raw HTML, 
if there's no need for PHP to execute (or, PHP could execute via the 'fake 
gif link' technique.. or via JS).

-d

On July 15, 2006 3:12 AM, Mark Jaquith Wrote:
| On Jul 14, 2006, at 11:20 PM, Scot Hacker wrote:
|
| > So I've inferred that caching is fully present and working.
| >
| > But I also  keep seeing references to WP-Cache 2, as if caching
| > were NOT already present in WP 2.
| >
| > What's the real caching deal?
|
| WP 2.0+ includes an object-caching system.  It caches data objects
| frequently used by WP, e.g. user data, category data, page data.  The
| system is pluggable, but has built-in support for caching to the
| filesystem.  This system was enabled by default in 2.0 and 2.0.1
|
| In 2.0.2, it was turned off, because certain setups were causing
| problems.  So now it has to be intentionally enabled in wp-config.php
| in order to work.
|
| This system, no matter what backend it uses (there are drop in
| backends for APC and Memcached), is not a substitute for WP-Cache2.
| The benefits of the built-in object cache are small, but WP-Cache2
| can give you several orders of magnitude more page-serving power,
| because it caches the HTML output of pages for a particular URL +
| Cookie combination.  Cached hits use no DB calls and very little
| processing power (as WP isn't fully loaded for the hit).
|
| Both systems offer speed and throughput benefits, and complement each
| other, as they cache different things.  The built-in cache speeds up
| your dynamic hits, and WP-Cache2 caches your dynamic hits so that
| subsequent hits use fewer resources.