I have two instances of SQL Server running on my laptop, one is SQL Server 2008 and the other is SQL Server 2008 R2. Now take a look at this image from task manager.
Can you tell which process is the 2008 instance and which process is the 2008 R2 instance? I can’t either. Now if you want to know what process id your instance is using you can do three things
1) Use T-SQL
Run the following query in a query window
I get the following as output when running that query on both instances
2212 10.0.2531.0 2184 10.50.1600.1
So, now I know that the 2008 instance is using processid 2212 and the 2008 R2 instance is using 2184
2) Look at the SQL Server log
If I look at my SQL Server log, I see the following
05/12/2010 08:24:25,System Manufacturer: ‘Hewlett-Packard’
05/12/2010 08:24:25,Server process ID is 2184.
05/12/2010 08:24:25,All rights reserved.
05/12/2010 08:24:25,© Microsoft Corporation.
05/12/2010 08:24:25,Microsoft SQL Server 2008 R2 (RTM) – 10.50.1600.1 (X64)
3) Use the services tab in task manager
This is probably the easiest one, just switch to the services tab