Dion

UsageDD allows administrators to monitor the resource usage of their WordPress installation. It will add a small box at the bottom center of each page, only visible to administrators, that displays the number of MySQL queries, the amount of memory used by the page’s code, and if you are using a compatible webserver (most are compatible), the “time to first byte” (TTFB) and the time required to generate the full page. TTFB is used by Google for page-ranking purposes, and it will be the first of the two displayed.
You can use the display to determine if your site has too many plugins loaded, if your theme is too “heavy”, or if something is wrong on your server. The plugin itself uses virtually no resources and should be compatible with every theme and plugin that outputs HTML.
Support is available in our <a href="https://forum.dion-designs.com/f35/usagedd-support/" rel="nofollow ugc">dedicated support area</a>. Support questions posted on wordpress.org may go unanswered for an extended period of time.

UsageDD

UsageDD allows administrators to monitor the resource usage of their WordPress installation.

Viktor Szépe

“It’s important to make resources (images, scripts, stylesheets, etc.) cacheable.”
<a href="http://www.stevesouders.com/blog/2008/08/23/revving-filenames-dont-use-querystring/" rel="nofollow ugc">Steve Souders</a>
It is much easier to use a CDN without Query String Parameters. 
This plugins alters only local resources’ URL-s. 
The <code>ver</code> Query String Parameter will be inserted into the filename.
For example <code>jquery.min.js?ver=1.10</code> becomes <code>jquery.min.110.js</code>.
To reverse this in the web server add this line to your nginx config:
<pre><code>server {
 location ~ ^(.+)\.\d\d+\.(js|css|png|jpg|jpeg|gif|ico)$ {
 #try_files $uri $1.$2 /index.php?$args;
 try_files $uri $1.$2 =404;
 }
}
</code></pre>
Or to your Apache configuration or <code>.htaccess</code> file.
<pre><code>RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.+)\.\d\d+\.(js|css|png|jpg|jpeg|gif|ico)$ $1.$2 [NC,L]
</code></pre>
<h4>Testing the plugin before live usage</h4>
You can test the plugin by replacing the two <code>add_filter()</code> calls with this
<pre><code>require_once( dirname( dirname( dirname( dirname( __FILE__ ) ) ) ) . '/wp-load.php' );
wp();
echo o1_revving_src( $argv[1] ) . PHP_EOL;
</code></pre>
Then start it from CLI: <code>php revving.php <TEST-URL></code>
<h4>Links</h4>
Development of this plugin goes on on <a href="https://github.com/szepeviktor/resource-versioning" rel="nofollow ugc">GitHub</a>.

Resource Versioning

Turn Query String Parameters into file revision numbers.

UsageDD vs Resource Versioning