I had the same problem, database expansion was very slow at Mng Studio 2012 and 2014, but not for 2008. The problem was that for many databases, the AutoClose property was set to True
I used this script to search these databases
SELECT name, is_auto_close_on, is_auto_shrink_on FROM master.sys.databases AS dtb WHERE is_auto_close_on = 1 OR is_auto_shrink_on = 1 ORDER BY name
And then I set the AutoClose property to False in these databases.
From now on, node databases expand instantly
George Vovos
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