Page History

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• Template cache. For better front-end performance, PrestaShop caches your HTML pages.
  • Never compile cacherecompile template files. Only enable this if you are making edits theme, and need to see your changes every time you reload your page.
  • Compile cache if templates are templates if the files have been updated. PrestaShop is able to see when a theme file has changed, but this might not always work as expected.
  • Force Compilecompilation. The normal behavior: HTML pages are compiled and cached, even if the theme has changed.
• Cache. This option makes it possible for you to disable all file caches, and not just the one pertaining to template files. Only disable this if you debugging a theme or a module for PrestaShop. Otherwise, you should leave it enabled.
  The "Clear Smarty cache" makes it possible to delete the cache in a single click instead of having to go delete files on your FTP server.
• Debug console. PrestaShop enables you to display the Smarty Debug Console, which gives you valuable information on a template page. Read more about it at http://www.smarty.net/docsv2/en/chapter.debugging.console.tpl. Note that the console opens in a pop-up window: make sure to make your browser allow them for your shop's domain name.
  
  • Do not open console. The default setting. No one sees the console, not even you.
  • Open console with URL parameter (SMARTY_DEBUG). The console is only displayed if you add ?SMARTY_DEBUG at the end of the URL (or the key of your choice, see below). This is great, but once your tests are done, do revert to the default setting, as this "trick" is known and some hackers could make use of it.
  • Always open console. The "full on" setting. Everyone who has access to your shop can see the console. Therefore, keep it for maintenance sessions.
• Debug console Key. You can change the key in order to be the only one to know what key to enter in order to display the debug console.

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You can disable the following catalog features:

• Combinations. Product combinations enable you to have a whole product line out of a single product: varying size, colors, capacity, etc.
• Features. Product features enable you to indicate the product's specific information: weight, material, country of origin, etc.
• Customer groups. Customer groups enable you to group customers in order to give them certain privileges and restrictions: discount, module restrictions, etc.

Combine, Compress and Cache (CCC)

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• Smart cache for CSS. CSS files are text-based, and can be safely combined and compressed.
• Smart cache for JavaScript. JavaScript files are also text-based, but their combination can sometimes prove problematic. Make sure to test everything before leaving that setting enabled.
• Minify HTML. The HTML code generated by Smarty can be minified, meaning that PrestaShop will remove all whitespace in order to save a few bytes. This is mostly safe.
• Compress inline JavaScript in HTML. Some themes have JavaScript code directly within. You can either leave it alone, or have them compressed. Again with JavaScript compression, make sure to test everything before leaving that setting enabled.
• High risk HTML compression. This option is marked as "high risk" because while the HTML code is very much compressed, it will not respect web-standards anymore. Use this at your own risk: some search engines do not deal well with websites that do not respect HTML standards, and this might make you lose your position in search results. Use with caution.
• Apache optimization. This setting will change your Web web server's configuration file in order to make them it more efficient for CCC.

Media servers

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• Use Rijndael with mcrypt lib. Default choice. Fast and secure, but requires you to have the Mcrypt extension installed with PHP.
• Keep the custom BlowFish class. Better security, but performance takes a toll, as it takes more time to validate the authentication, for each page load. Your customers might appreciate the added security, but might not like the time spent waiting for the page to load – although the time difference is really unnoticeable to most.

Therefore, choose wisely. If you change this configuration, all cookies will be reset.

Caching

Your server's cache stores static versions of your dynamic web page, in order to serve these to your customers and thus reduce server load and compiling time.

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This section enables you to choose to enable caching, and then choose the caching method:

• File system. The static files are simply stored as any other file, on your server. This displays a field set to "1" by default. This is the file-system directory depth. Only change this value when you know what you are doing.
  
• Memcached. A distributed caching system. Very effective, above all with multiple servers, but you need to make sure that your servers/hosts support it – most probably, if your PHP configuration features the Memcached PECL extension, you are good to go (you can download it here: http://pecl.php.net/package/memcache). You can add Memcached servers by clicking on the "Add server" link.
• APC. Alternative PHP Cache is free, open and robust, but only works with one server – which is the usual case when you start your online business. Again, check for the availability of the APC PECL extension on your server: http://pecl.php.net/package/APC.
• Xcache. Xcache is a new cache system, which is specific to the Lighttpd server – hence, it will not work with the popular Apache server. Read more about it at http://xcache.lighttpd.net/.
• File system. The static files are simply stored as any other file, on your server.

The last three options display a field set to "1" by default. This is the file-system directory depth. Only change this value when you know what you are doing.