SQL Server and Agent both run under LocalSystem.
Q1: In SSMS query window nog performance delay, its <1 second.
Q2: Yes, 12GB, 3GB free of RAM
Q3: Its virtual (hypervisor)
Q4: Installed 18.104.22.16800 this morning (SP1), still same issue
I've managed to narrow the problem, it looks like a delay on SQL Server Agent. When i reboot the SQL Server Agent through services it takes up to 45 seconds to stop the server and 5 seconds to start it. Same on my old SQL 2005 server is done under 10 seconds.
What causes the delay in stopping SQL Server Agent?
The sql server agent job runs under the credentials of the service account.
Question 1 - Do you have the same performance issue when logging into SSMS using that account?
The min / max memory settings are sometimes forgotten about when building out a new server.
Question 2 - Did you use the correct settings?
Question 3 - Is this a physical or virtual server that you have SQL Server installed on? If it is a virtual server, there can be issues with the ballon memory manager, I am not a VM expert.
Question 4 - Make sure you have the latest service pack and cummulative updates for SQL Server 2012.
Please answer these questions. It will give me a better idea of what you are dealing with.