we too are experiencing long page load times with the Krystle Theme. We often get the error shown below.
The page looks like it has loaded then becomes unresposive. The general sequence seems to be: when a page, often with a number of blocks is loading, 2 or 3 (previously docked) blocks go straight into the dock, the body text is in the middle of the page, with a block width margin to the left of the page where the blocks wuld normally display, all of the remaining blocks display on the righthand side of the main content (even some of the ones that are supposed to be docked), then the page seems to stall and is totally unresponsive, then the error above often pops up. Sometimes it goes away quickly by itself, other times you need to click the "stop script" button on the popup. The popup disappears & the page finishes loading almost instantly at times, at which point the body section jumps over to the left, and the other blocks from the right hand side that should have been in the dock now jump into the dock and hide there. The page then functions normally. Once this behaviour starts it generally repeats on every page load. Page loads can be frustratingly slow - especially when the page looks like it has loaded. It can cause problems too if a user clicks on a link - nothing happens, the body section then jumps over to the left, and the click then hits on some other link that is now under the previous mouse position - I have accidently deleted things by accident a few times in this way.
This is quite a frustrating problem and is very dependent on the pc being used. The more powerful the pc, the smaller the effect. Many of our students are using netbooks so they are effected quite significantly. Accross the board at school we are also required to use Internet Explorer by department policy.
This behaviour is most problematic with the Krystle theme, and to a lesser extent Decaf. All of the other themes that I have tried don't seem to behave this way, especially the core themes which all run well - The Krystle theme is by far our preferred theme and we would like to get this issue sorted out if possible.
Our site is Moodle 2.3.8+ (Build: 20130712), Krystle Theme 2013041600 (we have only changed the colours a little and included a site logo via the URL in the theme settings - no code changes at all).
Our server is quite new (Dell R715 (16GB RAM), running Ubuntu 12.04 LTS server, apache2 webserver, php5 version 126.96.36.199.3.7, postgresql 9.1.9 and APC php accelerator 3.1.7. The server is runnig behind the departments proxy server.
Thankyou in advance for your assistance.