I followed the general guidelines for configuring for PHP caching. All initially seemed fine with massive performance improvements.
However, I noticed after some time (around 30 minutes) that some pages were being served as complete garbage - looked like UTF8 issues. Lots of searching later and numerous changes to Super Cache config I am still no nearer a reliable solution.
I have disabled Preload as this appeared to be the initial source, although I'm not now convinced, since the issue still occurs.
I have tried with compression on and off.
I have tried with/without the following in the htaccess file:
# BEGIN compress content
AddOutputFilterByType DEFLATE text/plain
AddOutputFilterByType DEFLATE text/html
AddOutputFilterByType DEFLATE text/xml
AddOutputFilterByType DEFLATE text/css
AddOutputFilterByType DEFLATE application/js
AddOutputFilterByType DEFLATE application/xml
AddOutputFilterByType DEFLATE application/xhtml+xml
AddOutputFilterByType DEFLATE application/rss+xml
# remove browser bugs
BrowserMatch ^Mozilla/4 gzip-only-text/html
BrowserMatch ^Mozilla/4\.0 no-gzip
BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
Header append Vary User-Agent
# END compress content
Right now I have all caching turned off as I can not risk pages being served as meaningless characters. The result is the site is extremely slow and only marginally more useful than if it served garbage.
I am no expert but can follow simple instructions! Can some one please give some guidance?