I am trying to diagnose slow application performance on a client site.
A log file on the client machine tells me execution time for each query measured From the application side. It appears that many bare-bones simple queries to the remote DB are taking an exorbitant amount of time to complete. For example,
SELECT CONVERT(varchar, GETDATE(), 121)
This query is repeatedly taking over 5 seconds to execute as timed from the application. Other queries almost as simple (inserting one recordset into one table) are taking over a minute to complete. On my test system (with a copy of the client's database) I do not experience any of these problems.
I would suspect a slow network, except that the problem reliably disappears after running a report from Crystal Reports. Then after 1-2 hours the application slows down again.
For the sake of isolating the problem further, I would like to retrieve/log the execution time on the server side. I am trying to figure out what the best way of doing this is. I could use a variable to obtain the execution time for a single query, but I don't have the option of modifying every single query in my application.
sys.dm_exec_query_stats
looked very promising for retrieving execution times for previous queries, but the millisecond values it reports for last_elapsed_time seem far too high.
Can anyone help me figure out how to obtain timing for my queries?