I have set up canary queries for a couple of workloads with 'login each time query runs' option unchecked. I have also set up alerts for any users connected to the box for over 10 hours. Although the canaries are in place for three days now, I have only got one 10 hour connection time alert for the canary query user and that too after it has been connected to the box for over 24 hours.
Can someone tell me how many canary queries are run under each session or how long each session remain on the box? Is there a limit? How the session handling for canary queries work?
When the "Login each time query runs" option is unchecked, the Viewpoint data collecton service will try to get a session to Teradata from its connection pool. This is a shared connection pool between all collectors that run SQL against Teradata (assuming that the same login is used for each collector). There might or might not be an open and currently unused session in the pool when the canary query runs. So, with this option unchecked you don't know whether or not a new session will be created for each execution of the canary query.
When the "Login each time query runs" option is checked, the Viewpoint data collection service will not use a connection pool. Instead, it will open a new session for this particular execution of the canary query, and will close the session once the query completes.
Can you please let me know where do i look for this connection pool? i mean, is there any table where this is stored?
Thanks for the reply Steve. Although I think it is the case but just confirming that this connection pool is internally controlled and not visible and/or modifiable as such?
Correct, the connection pool is internally managed in the data collection service. A connection pool is a cache of open database connections that can be reused, thus preventing the collection service from having to open a new connection for every request. The connection pools in Viewpoint are not visible or modifiable.