監控tempdb使用硬碟空間對DBA來說相當重要
select * from testsort
order by c5
主要使用 dm_db_task_space_usage
;WITH task_space_usage AS (
-- SUM alloc/delloc pages
SELECT session_id,
request_id,
SUM(internal_objects_alloc_page_count) AS alloc_pages,
SUM(internal_objects_dealloc_page_count) AS dealloc_pages
FROM sys.dm_db_task_space_usage WITH (NOLOCK)
WHERE session_id =57--<> @@SPID
GROUP BY session_id, request_id
)
SELECT TSU.session_id,
TSU.alloc_pages * 1.0 / 128 AS [internal object MB space],
TSU.dealloc_pages * 1.0 / 128 AS [internal object dealloc MB space],
EST.text,
-- Extract statement from sql text
ISNULL(
NULLIF(
SUBSTRING(
EST.text,
ERQ.statement_start_offset / 2,
CASE WHEN ERQ.statement_end_offset < ERQ.statement_start_offset THEN 0 ELSE( ERQ.statement_end_offset - ERQ.statement_start_offset ) / 2 END
), ''
), EST.text
) AS [statement text],
EQP.query_plan
FROM task_space_usage AS TSU
INNER JOIN sys.dm_exec_requests ERQ WITH (NOLOCK)
ON TSU.session_id = ERQ.session_id
AND TSU.request_id = ERQ.request_id
OUTER APPLY sys.dm_exec_sql_text(ERQ.sql_handle) AS EST
OUTER APPLY sys.dm_exec_query_plan(ERQ.plan_handle) AS EQP
WHERE EST.text IS NOT NULL OR EQP.query_plan IS NOT NULL
ORDER BY 3 DESC, 5 DESC
搭配dm_io_virtual_file_stats 和 database_files 可進一步確認讀和寫大小
declare @read bigint, @write bigint;
select @read = SUM(num_of_bytes_read), @write = SUM(num_of_bytes_written)
from tempdb.sys.database_files AS DBFiles
join sys.dm_io_virtual_file_stats(2, NULL) AS FS
on FS.file_id = DBFiles.file_id
where DBFiles.type_desc = 'ROWS'
--查詢測試
select * from testsort
order by c5
select internal_useMB =
(
select internal_objects_alloc_page_count / 128.0
from sys.dm_db_task_space_usage
where session_id = 56--@@SPID
),
tempdb_readMB = (SUM(num_of_bytes_read) - @read) / 1024.0 / 1024.0,
tempdb_writeMB = (SUM(num_of_bytes_written) - @write) / 1024.0 / 1024.0
from tempdb.sys.database_files AS DBFiles
join sys.dm_io_virtual_file_stats(2, NULL) AS FS
on FS.file_id = DBFiles.file_id
where DBFiles.type_desc = 'ROWS'
參考