-- 查看性能记数器
SELECT * FROM sys.dm_os_performance_counters
-- 执行过的线程所遇到的所有等待(不是当前正在运行的线程, 为自上次重置统计信息或启动服务器以来累积的数据),可分析靠前的几个等待较高的事件。
select * from sys.dm_os_wait_stats order by wait_time_ms desc
该动态视图的细节，请查看帮助文档.
-- 重置该动态视图
DBCC SQLPERF ('sys.dm_os_wait_stats', CLEAR);
GO
-- 正在等待某些资源的任务的等待队列
select * from sys.dm_os_waiting_tasks order by wait_duration_ms desc
内存使用：
查看当前由 SQL Server 分配的内存对象(KB): select sum((page_size_in_bytes/1024)*max_pages_allocated_count) from sys.dm_os_memory_objects;
查看系统内存当前信息: select * from sys.dm_os_sys_memory (这个动态视图只在sql 2008中才有)
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
限制SQL Server使用的最小,最大内存(MB)：
sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO
sp_configure 'min server memory', 300;
GO
sp_configure 'max server memory', 850;
GO
RECONFIGURE;
GO
CPU使用情况:
SELECT TOP 50
total_worker_time/execution_count AS '每次执行占用CPU(微秒)',
execution_count as '执行次数',
total_worker_time as '总共占用CPU(微秒)',
creation_time as '创建时间',
last_execution_time as '最后执行时间',
min_worker_time as '最低每次占用CPU',
max_worker_time as '最高每次占用cpu',
total_physical_reads as '总共io物理读取次数',
total_logical_reads as '总共逻辑读取次数',
total_logical_writes as '总共逻辑写次数',
total_elapsed_time as '完成此计划的执行所占用的总时间(微秒)',
(SELECT SUBSTRING(text,statement_start_offset/2,(CASE WHEN statement_end_offset = -1 then LEN(CONVERT(nvarchar(max), text)) * 2 ELSE statement_end_offset end -statement_start_offset)/2) FROM sys.dm_exec_sql_text(sql_handle)) AS 'SQL内容'
FROM sys.dm_exec_query_stats
ORDER BY 1 DESC
--下面的查询显示SQL 等待分析和前10 个等待的资源
select top 10 *
from sys.dm_os_wait_stats
where wait_type not in ('CLR_SEMAPHORE','LAZYWRITER_SLEEP','RESOURCE_QUEUE','SLEEP_TASK','SLEEP_SYSTEMTASK','WAITFOR')
order by wait_time_ms desc;
SQL Server中的活动会话数:
exec sp_who 'active'
print @@rowcount
SQL Server等待情况
select * from sys.dm_os_waiting_tasks ; --当前等待事件
select * from sys.dm_os_wait_stats --历史等待次数,是sqlserver启动后的累计值,需使用下一条语句清空
DBCC SQLPERF ('sys.dm_os_wait_stats', CLEAR);
找出进程阻塞:
运行下面的查询可确定阻塞的会话
select blocking_session_id, wait_duration_ms, session_id from
sys.dm_os_waiting_tasks
where blocking_session_id is not null
spid 正在阻塞另一个 spid，可在数据库中创建以下存储过程，然后执行该存储过程。此存储过程会报告此阻塞情况。键入 sp_who 可找出 @spid；@spid 是可选参数。
create proc dbo.sp_block (@spid bigint=NULL)
as
select
t1.resource_type,
'database'=db_name(resource_database_id),
'blk object' = t1.resource_associated_entity_id,
t1.request_mode,
t1.request_session_id,
t2.blocking_session_id
from
sys.dm_tran_locks as t1,
sys.dm_os_waiting_tasks as t2
where
t1.lock_owner_address = t2.resource_address and
t1.request_session_id = isnull(@spid,t1.request_session_id)
以下是使用此存储过程的示例。
exec sp_block
exec sp_block @spid = 7
select sum((page_size_in_bytes/1024)*max_pages_allocated_count) from sys.dm_os_memory_objects;
select * from sys.dm_os_sys_info;
select * from sys.dm_os_performance_counters
A. 获取有关按平均 CPU 时间排在最前面的五个查询的信息
以下示例返回前五个查询的 SQL 语句文本和平均 CPU 时间。
SELECT TOP 5 total_worker_time/execution_count AS [Avg CPU Time],
SUBSTRING(st.text, (qs.statement_start_offset/2)+1,
((CASE qs.statement_end_offset
WHEN -1 THEN DATALENGTH(st.text)
ELSE qs.statement_end_offset
END - qs.statement_start_offset)/2) + 1) AS statement_text
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS st
ORDER BY total_worker_time/execution_count DESC;
B. 提供批处理执行统计信息
以下示例返回按批执行的 SQL 查询的文本，并提供有关它们的统计信息。
SELECT s2.dbid,
s1.sql_handle,
(SELECT TOP 1 SUBSTRING(s2.text,statement_start_offset / 2+1 ,
( (CASE WHEN statement_end_offset = -1
THEN (LEN(CONVERT(nvarchar(max),s2.text)) * 2)
ELSE statement_end_offset END) - statement_start_offset) / 2+1)) AS sql_statement,
execution_count,
plan_generation_num,
last_execution_time,
total_worker_time,
last_worker_time,
min_worker_time,
max_worker_time,
total_physical_reads,
last_physical_reads,
min_physical_reads,
max_physical_reads,
total_logical_writes,
last_logical_writes,
min_logical_writes,
max_logical_writes
FROM sys.dm_exec_query_stats AS s1
CROSS APPLY sys.dm_exec_sql_text(sql_handle) AS s2
WHERE s2.objectid is null
ORDER BY s1.sql_handle, s1.statement_start_offset, s1.statement_end_offset;
-- 数据库文件性能,文件io性能统计(必须重启sql server服务,才能清零该计数器)
select DB_NAME(database_id) DB_NAME, file_id,io_stall_read_ms ,num_of_reads
,cast(io_stall_read_ms/(1.0+num_of_reads) as numeric(10,1)) as 'avg_read_stall_ms'
,io_stall_write_ms,num_of_writes
,cast(io_stall_write_ms/(1.0+num_of_writes) as numeric(10,1)) as 'avg_write_stall_ms'
,io_stall_read_ms + io_stall_write_ms as io_stalls
,num_of_reads + num_of_writes as total_io
,cast((io_stall_read_ms+io_stall_write_ms)/(1.0+num_of_reads + num_of_writes) as numeric(10,1)) as 'avg_io_stall_ms'
from sys.dm_io_virtual_file_stats(null,null)
order by avg_io_stall_ms desc;
-- 查看分区表money，各个分区的行数和边界值.
select partition = $partition.分区函数名(userid)
,rows = count(*)
,minval = min(userid)
,maxval = max(userid)
from dbo.money with(nolock)
group by $partition.分区函数名(userid)
order by partition;