Title: [Plugin: WP Super Cache] www.example.com != example.com
Last modified: August 19, 2016

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# [Plugin: WP Super Cache] www.example.com != example.com

 *  [bob_wp](https://wordpress.org/support/users/bob_wp/)
 * (@bob_wp)
 * [15 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-wwwexamplecom-examplecom/)
 * Hi
 * Super Cache treats [http://www.example.com](http://www.example.com) differently
   than example.com. It is happy to cache example.com and serve it back at ~ 1,300
   pages per second. It serves [http://www.example.com](http://www.example.com) 
   at ~ 6 pages per second. Since they both are the same page that seemed a bit 
   odd. The relivant portion of the debug log shows:
 *     ```
       15:41:58 / Output buffer callback
       15:41:58 / Buffer is blank. Output buffer may have been corrupted by another plugin or this is a redirected URL. Look for text 'ob_start' in the files of your plugins directory.
       15:41:58 / No closing html tag. Not caching.
       15:41:58 / Sending 'Content-Type: text/html; charset="UTF-8"' header.
       ```
   
 * Since the pages are identical ob_start is not likely the issue here. I did check,
   none of the likely plugins appears has an ob_start. Since it *is* in a sense 
   a redirected URL, that’s more likely the problem in this case.
 * All the .htaccess stuff is straight from the “let me write it for you” wizard.
   Httpd.conf is indeed configured to look at the .htaccess file. Re-write rules
   are being used for caching. The tests were all run using Apache’s ab utility 
   running on an independent host. The site is running under multi site. The issue
   is the same weather the site involved is the main one or a mapped site. The MU
   plugin is (of course) wordpress-mu-domain-mapping. The site is set up for sub-
   directories rather than sub-domains. Server is Apache 2.2.x. The page being served
   in the “non-www” case has a time stamp from around midnight (= cache hit). The
   timestamp on the “www” case changes with each page refresh.
 * My concern is the “first page” hit on the site if it’s a www prefix. Once the
   first page is loaded, the browser switches over to the non-www and everything
   is going to go nice and fast. Unfortunately the response on that first hit is
   pretty important.
 * I’m guessing that I missed something simple, but it’s not clear what. I’d rather
   not just start randomly changing rewrite rules without some guidance.
 * Sorry if this has already been covered. Everything I found with a search lead
   to issues where ob_start was the issue.
 * Help!
 * Thanks
 * Bob

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Author [Donncha O Caoimh (a11n)](https://wordpress.org/support/users/donncha/)
 * (@donncha)
 * [15 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-wwwexamplecom-examplecom/#post-1748651)
 * It’s probably WordPress itself redirecting from www to without www. Add a .htaccess
   rule to do that instead and that first “www.” request will be much faster. The
   plugin doesn’t cache redirection requests so that could be why it’s slow.
 *  Thread Starter [bob_wp](https://wordpress.org/support/users/bob_wp/)
 * (@bob_wp)
 * [15 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-wwwexamplecom-examplecom/#post-1748652)
 * Hi
 * Ok, I didn’t want to blindly add rules without checking. The good old “it’s working
   now and I don’t want to break it”. I have since added Varnish into the mix, so
   there’s a whole other layer of “stuff” going on.
 * Bob

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘[Plugin: WP Super Cache] www.example.com != example.com’ is closed to
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 * ![](https://ps.w.org/wp-super-cache/assets/icon-256x256.png?rev=3506220)
 * [WP Super Cache](https://wordpress.org/plugins/wp-super-cache/)
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 * 2 replies
 * 2 participants
 * Last reply from: [bob_wp](https://wordpress.org/support/users/bob_wp/)
 * Last activity: [15 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-wwwexamplecom-examplecom/#post-1748652)
 * Status: not resolved