Limit SQL Temp Database Growth

Question

I ran into a serious problem on my production server, where the temporary DB grows exponentially. Is there a way to restore the tempDB space without restarting the SQL service?

Cheers Kannan.

Answer 1

I would ignore messages suggesting changing the recovery model or limiting the size of tempDB (!).

You need to track the actual reason for the growth.

If you have the default trace enabled (it is enabled by default, out of the box), you can retrospectively find out what caused the growth by running this:

--check if default trace is enabled
if  exists (select 1 from sys.configurations where configuration_id = 1568)
BEGIN

declare @defaultTraceFilepath nvarchar(256)

--get the current trace rollover file
select @defaultTraceFilepath = CONVERT(varchar(256), value) from ::fn_trace_getinfo(0)
where property = 2

SELECT ntusername,loginname, objectname, e.category_id, textdata, starttime,spid,hostname, eventclass,databasename, e.name 
FROM ::fn_trace_gettable(@defaultTraceFilepath,0)
      inner join sys.trace_events e
            on eventclass = trace_event_id
       INNER JOIN sys.trace_categories AS cat
            ON e.category_id = cat.category_id
where 
      databasename = 'tempDB' and 
      cat.category_id = 2 and --database category
      e.trace_event_id in (92,93) --db file growth

END

SQL Profiler . , , - .

SQL Server tempDB DMV:

-- This DMV query shows currently executing tasks and tempdb space usage
-- Once you have isolated the task(s) that are generating lots 
-- of internal object allocations, 
-- you can find out which TSQL statement and its query plan 
-- for detailed analysis
select top 10
  t1.session_id, 
  t1.request_id, 
  t1.task_alloc,
  t1.task_dealloc,  
  (SELECT SUBSTRING(text, t2.statement_start_offset/2 + 1,
          (CASE WHEN statement_end_offset = -1 
              THEN LEN(CONVERT(nvarchar(max),text)) * 2 
                   ELSE statement_end_offset 
              END - t2.statement_start_offset)/2)
     FROM sys.dm_exec_sql_text(sql_handle)) AS query_text,
 (SELECT query_plan from sys.dm_exec_query_plan(t2.plan_handle)) as query_plan
from      (Select session_id, request_id,
sum(internal_objects_alloc_page_count +   user_objects_alloc_page_count) as task_alloc,
sum (internal_objects_dealloc_page_count + user_objects_dealloc_page_count) as task_dealloc
       from sys.dm_db_task_space_usage 
       group by session_id, request_id) as t1, 
       sys.dm_exec_requests as t2
where t1.session_id = t2.session_id and 
(t1.request_id = t2.request_id) and 
      t1.session_id > 50
order by t1.task_alloc DESC

(.)

Answer 2

DBCC SHRINKFILE tempdb .

DBCC SHRINKFILE ('tempdev', 1) DBCC SHRINKFILE ('templog', 1)

sysfiles.

- , , . , , .

:

tempdb SQL Server

http://support.microsoft.com/kb/307487

Answer 3

In SIMPLE mode, the tempdb database log is constantly truncated and can never be copied. Therefore, check that it is in Easy Mode