/* 常规服务器动态管理对象包括： dm_db_*：数据库和数据库对象 dm_exec_*：执行用户代码和关联的连接 dm_os_*：内存、锁定和时间安排 dm_tran_*：事务和隔离 dm_io_*：网络和磁盘的输入/输出 */ --- 运行下面的 DMV 查询以查看 CPU、计划程序内存和缓冲池信息。 select cpu_count, hyperthread_ratio, scheduler_count, physical_memory_in_bytes / 1024 / 1024 as physical_memory_mb, virtual_memory_in_bytes / 1024 / 1024 as virtual_memory_mb, bpool_committed * 8 / 1024 as bpool_committed_mb, bpool_commit_target * 8 / 1024 as bpool_target_mb, bpool_visible * 8 / 1024 as bpool_visible_mb from sys.dm_os_sys_info --- 高I/O开销的查询 Identifying Most Costly Queries by I/O SELECT TOP 10 [Average IO] = (total_logical_reads + total_logical_writes) / qs.execution_count , [Total IO] = (total_logical_reads + total_logical_writes) , [Execution count] = qs.execution_count , [Individual Query] = SUBSTRING (qt.text,qs.statement_start_offset/2, (CASE WHEN qs.statement_end_offset = -1 THEN LEN(CONVERT(NVARCHAR(MAX), qt.text)) * 2 ELSE qs.statement_end_offset END - qs.statement_start_offset)/2) ,[Parent Query] = qt.text , DatabaseName = DB_NAME(qt.dbid) FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) as qt ORDER BY [Average IO] DESC; --- 高CPU开销的查询 Identifying Most Costly Queries by CPU SELECT TOP 10 [Average CPU used] = total_worker_time / qs.execution_count , [Total CPU used] = total_worker_time , [Execution count] = qs.execution_count , [Individual Query] = SUBSTRING (qt.text,qs.statement_start_offset/2, (CASE WHEN qs.statement_end_offset = -1 THEN LEN(CONVERT(NVARCHAR(MAX), qt.text)) * 2 ELSE qs.statement_end_offset END - qs.statement_start_offset)/2) , [Parent Query] = qt.text , DatabaseName = DB_NAME(qt.dbid) FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) as qt ORDER BY [Average CPU used] DESC; --- 高开销的缺失索引 Cost of Missing Indexes SELECT TOP 10 [Total Cost] = ROUND(avg_total_user_cost * avg_user_impact * (user_seeks + user_scans),0) , avg_user_impact , TableName = statement , [EqualityUsage] = equality_columns , [InequalityUsage] = inequality_columns , [Include Cloumns] = included_columns FROM sys.dm_db_missing_index_groups g INNER JOIN sys.dm_db_missing_index_group_stats s ON s.group_handle = g.index_group_handle INNER JOIN sys.dm_db_missing_index_details d ON d.index_handle = g.index_handle ORDER BY [Total Cost] DESC; --- 最常执行的查询 Identifying Queries that Execute Most Often SELECT TOP 10 [Execution count] = execution_count ,[Individual Query] = SUBSTRING (qt.text,qs.statement_start_offset/2, (CASE WHEN qs.statement_end_offset = -1 THEN LEN(CONVERT(NVARCHAR(MAX), qt.text)) * 2 ELSE qs.statement_end_offset END - qs.statement_start_offset)/2) ,[Parent Query] = qt.text ,DatabaseName = DB_NAME(qt.dbid) FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) as qt ORDER BY [Execution count] DESC; --- 重复编译的查询（plan_generation_num 指示该查询已重新编译的次数） select top 25 sql_text.text, sql_handle, plan_generation_num, execution_count, dbid, objectid from sys.dm_exec_query_stats a cross apply sys.dm_exec_sql_text(sql_handle) as sql_text where plan_generation_num > 1 order by plan_generation_num desc --- 服务器等待的原因 SQL Query Records Causes of Wait Times SELECT TOP 10 [Wait type] = wait_type, [Wait time (s)] = wait_time_ms / 1000, [% waiting] = CONVERT(DECIMAL(12,2), wait_time_ms * 100.0 / SUM(wait_time_ms) OVER()) FROM sys.dm_os_wait_stats WHERE wait_type NOT LIKE '%SLEEP%' ORDER BY wait_time_ms DESC; --- 读和写 Identifying the Most Reads and Writes SELECT TOP 10 [Total Reads] = SUM(total_logical_reads) ,[Execution count] = SUM(qs.execution_count) ,DatabaseName = DB_NAME(qt.dbid) FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) as qt GROUP BY DB_NAME(qt.dbid) ORDER BY [Total Reads] DESC; SELECT TOP 10 [Total Writes] = SUM(total_logical_writes) ,[Execution count] = SUM(qs.execution_count) ,DatabaseName = DB_NAME(qt.dbid) FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) as qt GROUP BY DB_NAME(qt.dbid) ORDER BY [Total Writes] DESC; --- 运行下面的 DMV 查询以查找 I/O 闩锁等待统计信息。 select wait_type, waiting_tasks_count, wait_time_ms, signal_wait_time_ms, wait_time_ms / waiting_tasks_count from sys.dm_os_wait_stats where wait_type like 'PAGEIOLATCH%' and waiting_tasks_count > 0 order by wait_type -- 查看SQL阻塞信息 with tmp as ( select * from master..sysprocesses t where t.blocked != 0 union all select b.* from master..sysprocesses b join tmp t on b.spid = t.blocked ) select t.spid, t.blocked, t.status, t.lastwaittype, t.waitresource, t.waittime, t.open_tran , DB_NAME(t.dbid) DbName, t.login_time, t.loginame, t.program_name, dc.text from (select spid from tmp group by spid) s join master..sysprocesses t on s.spid = t.spid cross apply master.sys.dm_exec_sql_text(t.sql_handle) dc --kill 53; -- 查看所有会话的状态、等待类型及当前正在执行SQL脚本 select t.spid, t.kpid, t.blocked, t.status, t.lastwaittype, t.waitresource, t.waittime, t.open_tran , DB_NAME(t.dbid) DbName, t.last_batch, t.loginame, t.program_name, t.hostname, t.hostprocess
, t.cmd, t.stmt_start, t.stmt_end, t.request_id, dc.text from master.sys.sysprocesses t
outer apply master.sys.dm_exec_sql_text(t.sql_handle) dc
where t.spid >= 50
select s.spid, s.kpid, s.blocked, s.hostname, s.hostprocess, s.program_name, s.loginame
, s.status, s.lastwaittype, s.waitresource, s.waittime
, t.transaction_id, t.name, t.transaction_begin_time, dc.text
from sys.sysprocesses s
join sys.dm_tran_session_transactions st on s.spid = st.session_id
join sys.dm_tran_active_transactions t on st.transaction_id = t.transaction_id
outer apply master.sys.dm_exec_sql_text(s.sql_handle) dc
---补充，查看所有会话当前持有和申请的锁资源(选择在特定的业务库执行，测试模拟，建议将隔离级别改为可重复读)
set transaction isolation level repeatable read
select l.request_session_id,
l.resource_type,
l.resource_subtype,
l.request_status,
l.request_mode,
l.resource_description,
db_name(l.resource_database_id) as dbName,
case l.resource_type
when 'database' then DB_NAME(l.resource_database_id)
when 'object' then object_name(l.resource_associated_entity_id)
else OBJECT_NAME(p.object_id)
end as obj_name,
p.index_id,
l.request_lifetime
from sys.dm_tran_locks l
left join sys.partitions p on l.resource_associated_entity_id = p.hobt_id
order by l.request_session_id, l.resource_type
---查看所有会话的 找到活动事务对应的执行语句 select dc.session_id, ds.login_name, ds.login_time, dc.connect_time, dc.net_transport, dc.client_net_address, ds.host_name, ds.program_name, case ds.status when 'sleeping' then '睡眠 - 当前没有运行任何请求 ' when 'running' then '正在运行 - 当前正在运行一个或多个请求 ' when 'Dormancy' then '休眠 – 会话因连接池而被重置，并且现在处于登录前状态' when 'Pre-connected' then '预连接 - 会话在资源调控器分类器中' end as status , ds.cpu_time as cpu_time_ms, ds.memory_usage*8 as memory_kb, ds.total_elapsed_time as total_elapsed_time_ms, case ds.transaction_isolation_level when 0 then '未指定' when 1 then '未提交读取' when 2 then '已提交读取' when 3 then '可重复' when 4 then '可序列化' when 5 then '快照' end '会话的事务隔离级别', dt.text from sys.dm_exec_connections dc --执行连接，最近执行的查询信息 cross apply sys.dm_exec_sql_text(dc.most_recent_sql_handle) dt join sys.dm_exec_sessions ds on dc.session_id=ds.session_id where ds.login_name= 'LCGS609999' --where ds.program_name = '.Net SqlClient Data Provider' ORDER BY dt.text
--清除buffer pool里的所有缓存数据
DBCC DROPCLEANBUFFERS
GO
--清除buffer pool里的所有缓存的执行计划
DBCC FREEPROCCACHE
GO
--统计信息、执行计划
SET STATISTICS IO ON
SET STATISTICS TIME ON
SET STATISTICS PROFILE ON
-- 检查分析死锁信息 1、使用sql profiler 抓取死锁链及图 2、跟踪分析SQL ErrorLog日志 dbcc traceon (1204, 3605, -1) go dbcc tracestatus(-1) go 参考资料： http://support.microsoft.com/zh-cn/kb/832524 -- 检查分析闩锁等阻塞信息 WHILE 1=1 BEGIN EXEC master.dbo.sp_blocker_pss80 -- or sp_blocker_pss08 -- Or for fast mode -- EXEC master.dbo.sp_blocker_pss80 @fast=1 -- Or for latch mode -- EXEC master.dbo.sp_blocker_pss80 @latch=1 WAITFOR DELAY '00:00:15' END GO cmd执行命令： osql -E -Sserver -icheckblk.sql -ocheckblk.out -w2000 参考资料： http://support.microsoft.com/zh-cn/kb/271509
揭开隐藏数据的面纱，优化应用程序性能
https://msdn.microsoft.com/zh-cn/magazine/cc135978.aspx
