PortalProdigy's New Page Caching Dramatically Improves Website Performance
Posted on 10/19/2012
How PortalProdigy's Caching Works
Created Oct. 18, 2012
Caching is mechanism to make your website load faster. The performance improvement from caching can be dramatic.
How it works:
When PortalProdigy builds a page for the first time it stores a copy of it on the web server in what is called the "cache". Thereafter each time the page is requested, PortalProdigy delivers it from the cache; eliminating the time it takes to build the page from scratch0.
Although the concept of caching is simple, the process of maintaining the cash is complex. There are many issues. First and foremost is the issue of determining when the pages need to be re-built. Another issue is how to deal with dynamic content such as the user's name in a welcome or login widget, the items listed in shopping cart widget, or the customer specific pricing listed on a product detail page.
PortalProdigy uses a variety of techniques to maintain the cache and deliver dynamic content within pages. Dynamic content such a user's name must be rebuilt for each page request. When PortalProdigy retrieves a page from the cache that contains dynamic content it is aware of this and must perform a partial rebuild of the page. This process requires it to parse the cached page and update just the sections containing dynamic content. This is much faster than rebuilding the entire page.
Anytime a Widget is added or updated via Design Mode, PortalProdigy deletes all cached pages using the Widget. Actually it does not physically delete the cached page, but it marks it as deleted in the database, achieving the same result with less overhead.
Anytime a profile is saved in Page Manager all pages using the Profile are deleted from the cache. Anytime Site Settings are saved all cached pages are deleted.
Operations such as adding records, editing records, deleting records, and importing records do not update the cache. Thus if you add new product items and assign them to various product categories and product widgets, the cached pages will not be affected. You might be asking yourself why not? It's because it is too complex to determine what to update and what not to. It is much simpler and more reliable to simple delete the entire cache. When you are finished making changes to records you should go to Site Settings and click Save. You should make all your record changes first then save the Site Settings one time.
Any time you make a change and the change is not reflected on the page where it should be, the first thing to do is to go to Site Settings and click save. This should make the changes available. Also keep in mind that browser's cache resource files including pictures, java scripts, and CSS style sheets. Thus you may have to clear your browser's cache as well.