<div>CSS aggregation is cached and does not refresh until cache is cleared. Thus, when you make a change to a CSS file it is not evident until you clear the Drupal cache.</div><div><br></div>One of the biggest factors in front-end performance is reducing the number of requests the browser has to make in a single page load. With non-aggregated CSS files, the browser has to make a separate HTTP request for every single file, which contributes to the overall page load time. It is imperative to front-end performance that you aggregate CSS and JS files in a production environment.<div>
<br></div><div>Using a tool like yslow or Firebug's Net tab can give you an idea of how many requests are being made.</div><div><br></div><div>Further methods to reduce requests are to aggregate remote JS files locally, and use image sprites on CSS background images to reduce the number of images.</div>
<div><br></div><div>Ancillary to the performance concern is the fact that America's sweetheart, Internet Explorer, refuses to read more than 32 stylesheets (and I *believe* 200 kB of CSS?). I don't particularly mind this bug since it is a firm reminder to always turn on aggregation.</div>
<div><br></div><div><br><div class="gmail_quote">On Mon, Aug 15, 2011 at 9:09 PM, <span dir="ltr"><<a href="mailto:tony@tony-mac.com">tony@tony-mac.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
It is defined as "Aggregate and compress CSS files"<br>
Yet the effect was to ignore all the changes I made to the css files! Por que?<br>
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-----Original Message-----<br>
</div><div class="im">From: Edison Wong <<a href="mailto:hswong3i@gmail.com">hswong3i@gmail.com</a>><br>
Sender: <a href="mailto:support-bounces@drupal.org">support-bounces@drupal.org</a><br>
</div><div class="im">Date: Tue, 16 Aug 2011 08:01:44<br>
To: <a href="mailto:support@drupal.org">support@drupal.org</a><<a href="mailto:support@drupal.org">support@drupal.org</a>><br>
Reply-To: <a href="mailto:support@drupal.org">support@drupal.org</a><br>
</div>Cc: <a href="mailto:support@drupal.org">support@drupal.org</a><<a href="mailto:support@drupal.org">support@drupal.org</a>><br>
<div class="im">Subject: Re: [support] Theme css<br>
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