Resource Throttling in SharePoint 2010

List Threshold and throttling is a new feature in SharePoint 2010 lists.  This allow SharePoint administrator to block running heavy queries on SharePoint Lists which has thousands of items.  In SharePoint 2007 the max items that can be returned by a list view was about 2000 items and any query over that number can result in low performance and load on the server.  SharePoint 2010 lists has been optimized to support millions of items all together but provide SharePoint Administrators control over how many items are being retrieved from the lists at a time using User Interface or Object Model.

See the example below as we have a list with 6000 thousand items.  The default threshold limit is 5000 which can be changed in the Web Application Settings.

To set the resource throttling we need to go to Central Administration –> Application Management –> Manage Web application

click on the web application –> Click on the Ribbon and click the General settings Dropdown –> Select Resource Throttlling

There are different threshold values that we can specify List View Threshold  – Minimum Items before Thread hold – Default is 5000 Object Model Override – Do you want to allow object model code to override the threshold and run an expensive query.  Default is Yes List View Threshold for Auditors and Administrators – Maximum number of items in a view for a user who has sufficient permissions – Default is 20000 List View Lookup Threshold  -  The max number of columns that can be returned by a object model SPQuery.  Default is 6 Move-over you can also specify the time when you want to allow these expensive queries to run.

Now when a list has items mover than the threshold.  The settings page will show that the list has reached its threshold.

Go got List Settings using the ribbon.

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