如何避免MSSQL中的“休眠”进程？

Question

Currently I'm experiencing alot of issues with Server Processes (Seen from sp_who2) that is "sleeping" instead of just, finishing (being removed), when I connection to my MSSQL Database, calls a Stored Procedure, get some data and then closing the connection.

What's the best way in C#/.NET to connect to a MSSQL database, call a Stored Procedure, retrieve data from the Stored Procedure (Data Reader) and then close the connection?

Is there a way to close/dispose so that the "sleeping" processes gets killed?

Does it have something to do with me creating new SqlConnections, opening them and closing them all the time?

My flow is as follows:

A request occur:

1. I create a new SqlConnection Instance that connects to my MSSQL Database.
2. I call a Stored Procedure, retrieve the data and presents it to the user.
3. I close the Connection with .Close();
4. I repeat all these steps for each request. Requests happen once every 5-10 seconds. (Sometimes slower, sometimes faster)

I'm sorry If this question is missing some details, but I hope this is enough to get a some what helpful answer.

Thanks!

Answer 1

you need to use SET XACT_ABORT ON or add some client rollback code

When a client timeout event occurs (.net CommandTimeout for example), the client sends an "ABORT" to SQL Server. SQL Server then simply abandons the query processing. No transaction is rolled back, no locks are released.

Now, the connection is returned to the connection pool, so it isn't closed on SQL Server. If this ever happens (via KILL or client reboot etc) then the transactions+locks will be cleared. Note that sp_reset_connection won't or doesn't clear them, even though it is advertised to do so

This detritus from the abort will block other processes.

The way to make SQL Server clear transactions+locks on client timeout (strictly, ABORT events) is to use SET XACT_ABORT ON.

You can verify this be opening 2 query windows in SSMS:

Window 1:

In menu Query..Query Options set a timeout of 5 seconds then run this

BEGIN TRAN
UPDATE sometable WITH (TABLOCKX) SET foo = foo WHERE 1 = 0;
WAITFOR DELAY '00:00:10' -- just has to be longer then timeout

Window 2, this will wait forever (or hit your timeout)

SELECT * FROM sometable