Configuration Manager requires SQL Server to reserve a minimum of 8 gigabytes (GB) of memory for the central administration ...

Configuration Manager requires SQL Server to reserve a minimum of 8 gigabytes (GB) of memory for the central administration site and primary site and a minimum of 4 gigabytes (GB) for the secondary site. This memory is reserved by using the Minimum server memory setting under Server Memory Options and is configured by using SQL Server Management Studio. For more information about how to set a fixed amount of memory, see http://go.microsoft.com/fwlink/p/?LinkId=233759.