SharePoint Best Practices for Performance Tuning

Rule 1:	Dispose site/web object
	SPSite/SPWeb – Bad Practice
	SPSite oSPsite = new SPSite(“http://server”); SPWeb oSPWeb = oSPSite.OpenWeb(); str = oSPWeb.Title; // bad practise since object are not disposed.
	In this case, You never dispose SPSite and SPWeb. Its memory leak.
	SPSite/SPWeb – Good Practice
	String str;using(SPSite oSPsite = new SPSite(“http://server”)) { using(SPWeb oSPWeb = oSPSite.OpenWeb()) { str = oSPWeb.Title; } }
	You can automatically dispose of SharePoint objects that implement the IDisposable interface by using the Microsoft Visual C# using statement

Rule 2:	Do not Dispose current site/web object
	SPSite/SPWeb – Bad Practice
	using(SPSite oSPsite = SPContext.Current.Site) //bad practice { using(SPWeb oSPWeb = SPContext.Current.Web) //bad practice { str = oSPWeb.Title; } }
	Do not dispose current context object
	SPSite/SPWeb – Good Practice
	String str;SPSite oSPsite = SPContext.Current.Site; SPWeb oSPWeb = SPContext.Current.Web; str = oSPWeb.Title;
	You can automatically dispose of SharePoint objects that implement the IDisposable interface by using the Microsoft Visual C# using statement

Rule 3:	Get SPList Object
	SPWeb.Lists (“name”) – style="color: #ff0000;">Bad Practice
	using (SPSite site = new SPSite(strSite)) { using (SPWeb web = site.OpenWeb()) { SPList oList = web.Lists ["MyList"] } }
	In this case, it loads the metadata* of the all lists in that specific SPWeb object.
	SPWeb.GetList (string strUrl) – Good Practice
	using (SPSite site = new SPSite(strSite)) { using (SPWeb web = site.OpenWeb()) { SPList oList = web.GetList(“/list/AllItem.aspx”) } }
	In this case, it loads the metadata* of the all lists in that specific SPWeb object.

Rule 4:	Get SPListItem Object
	SPList.Items[int idx] – style="color: #ff0000;">Bad Practice
	using (SPSite site = new SPSite(strSite)) { using (SPWeb web = site.OpenWeb()) { SPList oList = web.GetList(“http://Site/list/AllItem.aspx”); for(int idx =0; idx< oList.ItemCount; idx ++) { string strLstItemName = oList.Items[idx].Name; } } }
	In this case, for each iteration oList.Item[idx] will load a SPListItemCollection.
	SPListItemCollection[int idx] – Good Practice
	using (SPSite site = new SPSite(strSite)) { using (SPWeb web = site.OpenWeb()) { SPList oList = web.GetList(“http://Site/list/AllItem.aspx”); SPListItemCollection oListItems = oList.Items; for(int idx =0; idx< oList.ItemCount; idx ++) { string strLstItemName = oListItems[idx].Name; } } }
	In this case, in the memory this code will load only one SPListItemCollection

Rule 5:	SPListItem in Event Handler
	SPListItem – Bad Practice
	public override void ItemAdded(SPItemEventProperties properties) { using (SPSite oSite = new SPSite(properties.WebUrl)) { using (SPWeb oWeb = oSite.OpenWeb()) { SPList oList = oWeb.Lists[properties.ListId]; SPListItem oListItem = oList.GetItemByUniqueId(properties.ListItemId); } } }
	In this case, we are unnecessarily giving extra load to the memory by adding so many memory consuming APIs
	SPListItem – Good Practice
	public override void ItemAdded(SPItemEventProperties properties) { SPListItem oItem = properties.ListItem; }
	In this case, we have reduced lots of code and it will return the current ListItem by using “proerties”

Rule 6:	item count
	SPList.Item.Count – Bad Practice
	using (SPSite site = new SPSite(strSite)) { using (SPWeb web = site.OpenWeb()) { SPList oList = web.GetList(“http://Site/list/AllItem.aspx”); int iCount = oList.Items.Count; } }
	In this case, oList.Items.Count, first it will load all the SPListItems in the memory and then it will find out the total count.
	SPList.Item.ItemCount – style="color: #339966;">Good Practice
	using (SPSite site = new SPSite(strSite)) { using (SPWeb web = site.OpenWeb()) { SPList oList = web.GetList(“http://Site/list/AllItem.aspx”); int iCount = oList.ItemsCount; } }
	In this case, ItemCount is a part of metadata of the SPList object and this will get generated whenver we create a SPList instance

Rule 7:	Applying Lock
	Cache – Bad Practice
	public void CacheData() { SPListItemCollection oListItems;oListItems = (SPListItemCollection)Cache["ListItemCacheName"]; if(oListItems == null) { oListItems = DoQueryToReturnItems(); Cache.Add(“ListItemCacheName”, oListItems, ..); // bad practice }}
	Although the use of the cache in this example is functionally correct, because the ASP.NET cache object is thread safe, it introduces potential performance problems
	Cache with lock – Good Practice
	private static object _lock = new object();public void CacheData() { SPListItemCollection oListItems;lock(_lock) // Good Practice { oListItems = (SPListItemCollection)Cache["ListItemCacheName"]; if(oListItems == null) { oListItems = DoQueryToReturnItems(); Cache.Add(“ListItemCacheName”, oListItems, ..); } } }
	In this case, you do not need to suspend all threads while checking to see if the data is already cached.

Rule 8:	SPQuery
	SPQuery – Bad Practice
	SPQuery query = new SPQuery(); SPListItemCollection spListItems ;StringBuilder sb = new StringBuilder(); sb.Append(“<OrderBy Override=”TRUE”><FieldRef Name=”ID”/></OrderBy>”); //.. Append more text as necessary .. query.Query = sb.ToString();spListItems = spList.GetItems(query);
	Although the use of SPQuery is good but its increase performance since its does not use rowlimit, viewfields
	SPQuery – Good Practice
	SPQuery query = new SPQuery(); SPListItemCollection spListItems ;// Include only the fields you will use. query.ViewFields = “<FieldRef Name=”ID”/><FieldRef Name=”ContentTypeId”/>”; query.RowLimit = 200; // Only select the top 200.StringBuilder sb = new StringBuilder(); sb.Append(“<OrderBy Override=”TRUE”><FieldRef Name=”ID”/></OrderBy>”); //.. Append more text as necessary .. query.Query = sb.ToString();spListItems = spList.GetItems(query);
	In this case, You use SPQuery which has rowlimit and view fields. This increase performance

Table 1. Alternatives to SPList.Items
Poor Performing	Better Performing
Methods and Properties	Alternatives
SPList.Items.Count	SPList.ItemCount
SPList.Items[System.Guid]	SPList.GetItemByUniqueId(System.Guid)
SPList.Items[System.Int32]	SPList.GetItemById(System.Int32)
SPList.Items.GetItemById(System.Int32)	SPList.GetItemById(System.Int32)
SPList.Items.ReorderItems (System.Boolean[],System.Int32[],System.Int32)	Perform a paged
	query by using SPQuery and reorder the items within
	each page.
SPFolder.Files.Count	SPFolder.ItemCount
SPList.Items.XmlDataSchema	Create an SPQuery
	object to retrieve only the items you want.
SPList.Items.NumberOfFields	Create an SPQuery
	object (specifying the ViewFields)
	to retrieve only the items you want.