Kill a SQL Server SPID and Check Rollback Progress

Problem

From time to time, I encounter blocking situations where I end up issuing a SQL KILL command against the blocking SPID (Server Process ID). When I run sp_who2, I can see the killed SPID is in a ROLLBACK state. Is there any way I can get an idea of how long the rollback for the SPID will take?

Solution

There sure is! The SQL KILL command offers the WITH STATUSONLY argument which displays an estimation of completion for an in progress ROLLBACK. Using KILL with this argument does not kill a connection; it simply produces a progress report.

SQL Server Blocking Scenario

Run the following script in a new SQL Server Management Studio query window. It captures the connected SPID for the query and displays the fact that the SPID has an open transaction when the script completes:

set nocount on
go 
select 'SPID = ' + cast(@@spid as varchar) -- what connection is this?
go
 
create table test (col1 int identity) -- create a test table
go
 
begin tran tran1 -- start a transaction
 
while (1 = 1)
begin
   insert test default values
   if scope_identity() > 999999 -- break after inserting 1m rows
      break
end
go
dbcc opentran(0)
go
sql query

Kill SQL SPID

Now open a new connection and issue the following statements to kill the connection we just opened and to examine the connection’s state:

kill 52
go
exec sp_who2
go
rollback

SQL KILL with STATUSONLY

Now that we’ve KILLed the SPID, we can monitor its rollback progress by issuing KILL using the WITH STATUSONLY argument.

kill 52 with statusonly 
jester

As you can see, you can get a good estimation from the server of rollback progress.

Next Steps

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