You publish a Microsoft Excel workbook that contains some calculated measures or members to Microsoft SharePoint.
You connect the Excel workbook to another PowerPivot workbook.
You create a custom timer job that updates PowerPivot-based data in Excel Services for Microsoft SharePoint Server 2013.
You start the job.
In this scenario, the custom timer job stops when the progress indicator reaches about 10 percent, and then Excel Services freezes. Note The default maximum number of sessions in the Excel Services Application item in the Global Settings section is not changed.
This issue occurs because the online analytical processing (OLAP) provider that is connected to the data source opens a new Excel Services session for every connection that the OLAP provider tries to create. During the timer job run-time, Excel Calculation Services (ECS) opens too many connections to update the data. Therefore, ECS exceeds the maximum sessions-per-user threshold.
To work around this issue, increase the maximum sessions-per-user threshold. To do this, follow these steps:
In the Application Management section on the Central Administration home page, click Manage service applications.
On the Management Service Applications page, click Excel Services.
On the Manage Excel Services page, click Global Settings.
In the Session Management section, increase the maximum sessions-per-user threshold.
ECS opens a connection for each pivot cache when the PivotTable has a session state. If you create session members or measures, ECS creates a separate connection for the pivot caches. Additionally, the pivot caches do not share the connections so that the pivot caches do not connect to the same data source. ECS recognizes that too many connections are open when the underlying data source is a PowerPivot model that is contained in another workbook. When a PowerPivot model that is contained in another workbook is the data source for a connection, the OLAP provider that ECS uses to connect to the data source opens a new Excel Services session for every connection that Excel Services tries to create. Therefore, a workbook that contains many pivot caches that have a session state creates a connection and a new session for every pivot cache.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.