1. Performance optimization and caching in Kentico CMS Martin Hejtmanek (CTO), martinh@kentico.commartinh@kentico.com Webinar 9/16/2009

2. Topics  Caching options in Kentico CMS  Using caching in your code  The difference between good and bad code  SQL debug options  Cache debug options  ViewState debug options  Designing the right structure of the web site  Most common mistakes and how to avoid them

3. Caching options in Kentico CMS  Page info caching – Basic document information  Content caching – Content data for the controls  Partial caching – since 4.1  Full page (output) caching  Image (file) caching – GetFile etc.  API – CacheHelper http://devnet.kentico.com/Blogs/Martin-Hejtmanek/April-2009 /Deep-Dive---Kentico-CMS-Caching.aspx  Motto: Cache everything you can or wait for your pages to load!

4. Using caching in your code  Standard way (multiline) object result = null; string useCacheItemName = "myCacheKey"; if (!CacheHelper.TryGetItem(useCacheItemName, out result)) { // Get the data result = TreeHelper.SelectNodes("/%", false, "CMS.News"); // Save the result to the cache CacheHelper.Add(useCacheItemName, result, null, DateTime.Now.AddMinutes(10), System.Web.Caching.Cache.NoSlidingExpiration); }  Complex way (singleline) DataSet resultComplex = DataCacheHelper.GetCached3 ("/%", false, "CMS.News", TreeHelper.SelectNodes, "myKeyComplex", 10, false, null, null);

5. Good vs. bad code (1)  Bad code TreeProvider tree = new TreeProvider(); DataSet ds = tree.SelectNodes(CMSContext.CurrentSite.SiteName, "/News/%", CMSContext.PreferredCultureCode, false, null, null, null, -1, true); foreach (DataRow dr in ds.Tables[0].Rows) { tree = new TreeProvider(); int nodeId = ValidationHelper.GetInteger(dr["NodeID"], 0); TreeNode node = tree.SelectSingleNode(nodeId); ltlResponse.Text += node.GetValue("NewsTitle") + " "; }  Using complete context object to get simple value (SiteName)  Creating new TreeProvider for every item  Calling subqueries in the loop (SelectSingleNode)  Creating unnecessary objects to get values (SelectSingleNode)

6. Good vs. bad code (2)  Better code TreeProvider tree = new TreeProvider(); string siteName = CMSContext.CurrentSiteName; DataSet ds = tree.SelectNodes(siteName, "/News/%", CMSContext.PreferredCultureCode, false, null, null, null, -1, true); foreach (DataRow dr in ds.Tables[0].Rows) { string aliasPath = ValidationHelper.GetString(dr["NodeAliasPath"], ""); string className = ValidationHelper.GetString(dr["ClassName"], ""); TreeNode node = tree.SelectSingleNode(siteName, aliasPath, CMSContext.PreferredCultureCode, false, className); ltlResponse.Text += node.GetValue("NewsTitle") + " "; }  Calling subqueries in the loop (SelectSingleNode) – less  Creating unnecessary objects to get values (SelectSingleNode)

7. Good vs. bad code (3)  Best code TreeProvider tree = new TreeProvider(); DataSet ds = tree.SelectNodes(CMSContext.CurrentSiteName, "/News/%", CMSContext.PreferredCultureCode, false, "CMS.News", null, null, -1, true); foreach (DataRow dr in ds.Tables[0].Rows) { ltlResponse.Text += dr["NewsTitle"] + " "; }  Only single query, no other queries needed for the items  Motto: There is always a way how to make things better.

8. SQL debug options  web.config:  Site manager -> Administration -> System -> SQL debug

9. Cache debug options  web.config  Site manager -> Administration -> System -> Cache debug

10. ViewState debug options  web.config  Site manager -> Administration -> System -> ViewState debug

11. The right structure of the web site (1)  Which news was released first on 9/16/2002 ?  How many news were released in August ?  Which of the sites structures feels better? Site (CMS.Root) News (Page.MenuItem) News 1 (CMS.News) News 2 News 3 News 4 News 5 News 6 … News 1000 … News 12345 Site 2 (CMS.Root) News (Page.MenuItem) 2002 (Custom.NewsYear) August (Custom.NewsMonth) News 1 (CMS.News) … News 4 September News 5 … News 123 2009 September News 12345

12. The right structure of the web site (2)  Questions before you start designing the web site:  What is the purpose of the web site?  How will it’s life cycle look like?  How many documents and in what time frame will be there?  What information will you need to display and report?  What your boss (client) may want to implement in the future?  80/20 - 80% of the development are the 20% of the features (the ones that weren’t addressed by the original requirements) – minimize that  Phase 2 – How to ask for the pay rise for being more productive than others  How does the typical visitor behave? (which pages must be fastest)  Is the URL friendly enough (can you see the logical structure in it)?  Does the designed content structure allow this behavior?  Which best type of cache can be used for particular sections?

13. Most common mistakes  Not taking care about performance at all (nothing is automatic)  Relying on the basic API to cache things (not everything can be cached natively)  Creating the same objects over and over (TreeProvider, Connection)  Using way too many loops (most things can be done in a single pass)  Being too lazy to work with “low-level” objects such as DataRow (new and nicer objects mean more overhead)  Being too lazy to use methods with more parameters or overlook them (the more the method gets, the less needs to get from DB)  Overlooking that you already have the the required information available (querying API for things that are already in your original DataSet)  Not doing load tests before the site is live (it is like checking if the wine is poisoned by drinking it and see what happens)

14. Q&A  Now is the time for your questions  The webinar recording will be available on our new Partner portal and later on the DevNet.