Set Max Pool Size in SQL 2012 Reporting Services?

I don't see a place where you can adjust the pool size in SQL 2012 Reporting Services.  Yet I get the error below.  Is this error a red herring?

ERROR: Throwing Microsoft.ReportingServices.Library.ReportServerDatabaseUnavailableException: , Microsoft.ReportingServices.Library.ReportServerDatabaseUnavailableException: The report server cannot open a connection to the report server database. A connection to the database is required for all requests and processing. ---> System.InvalidOperationException: Timeout expired.  The timeout period elapsed prior to obtaining a connection from the pool.  This may have occurred because all pooled connections were in use and max pool size was reached.