Question

从生产站点上的ASP.NET前端环境调用此存储过程时，我有中间超时。它返回以下sql异常：

异常详细信息：System.Data.SqlClient.SqlException：Timeout 过期。在完成之前经过了超时时间操作或服务器没有响应。

有趣的是，在服务器上执行此过程时，或使用Management Studio从远程PC执行此过程时，它将在6秒内执行。但是，有时候从ASP.NET应用程序执行时会超时吗？这个查询可以改进吗？或者这个问题与其他问题有关吗？有谁可以提供帮助？我已经阅读了一些关于增加超时并在我的web.config中启用连接字符串池的线程，但还没有尝试过。

 ALTER PROCEDURE [dbo].[Report_Activity]
    (
        @StartDate      DATETIME
    ,   @EndDate        DATETIME
    ,   @TotalActions INT OUTPUT
    )

    AS
    BEGIN 

        SELECT      @TotalActions = COUNT(EventHistoryId)
        FROM        dbo.SessionEventHistory
        WHERE       DateCreated BETWEEN @StartDate AND @EndDate

        SELECT      EventDescription, COUNT(EventHistoryId) AS EventCount           
        FROM        dbo.SessionEventHistory
        WHERE       DateCreated BETWEEN @StartDate AND @EndDate
        GROUP BY    EventDescription
        ORDER BY    EventDescription

SQL SCHEMAS：

CREATE TABLE [dbo].[SessionEventHistory](
    [EventHistoryID] [int] IDENTITY(1,1) NOT NULL,
    [SessionHistoryID] [int] NOT NULL,
    [CategoryID] [int] NULL,
    [UserName] [nvarchar](50) NULL,
    [IPAddress] [nvarchar](20) NOT NULL,
    [EventDescription] [nvarchar](1000) NOT NULL,
    [EventData] [varbinary](max) NULL,
    [DateCreated] [datetime] NOT NULL,
 CONSTRAINT [PK_UserEventHistory] PRIMARY KEY CLUSTERED 
(
    [EventHistoryID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

GO

ALTER TABLE [dbo].[SessionEventHistory] ADD  CONSTRAINT [DF_UserEventHistory_DateCreated]  DEFAULT (getdate()) FOR [DateCreated]
GO

表有3个索引：

/****** Object:  Index [IX_SessionEventHistory_SessionHistoryId_CategoryId]    Script Date: 07/04/2012 10:47:06 ******/
CREATE NONCLUSTERED INDEX [IX_SessionEventHistory_SessionHistoryId_CategoryId] ON [dbo].[SessionEventHistory] 
(
    [SessionHistoryID] ASC,
    [CategoryID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
GO


/****** Object:  Index [IX_SessionEventHistory_UserName_DateCreated]    Script Date: 07/04/2012 10:47:09 ******/
CREATE NONCLUSTERED INDEX [IX_SessionEventHistory_UserName_DateCreated] ON [dbo].[SessionEventHistory] 
(
    [UserName] ASC,
    [DateCreated] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
GO


/****** Object:  Index [PK_UserEventHistory]    Script Date: 07/04/2012 10:47:14 ******/
ALTER TABLE [dbo].[SessionEventHistory] ADD  CONSTRAINT [PK_UserEventHistory] PRIMARY KEY CLUSTERED 
(
    [EventHistoryID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
GO

修改

我添加了以下索引，它看起来没问题吗？

CREATE NONCLUSTERED INDEX [IX_SessionEventHistory_DateCreated] ON [dbo].[SessionEventHistory] 
(
    [DateCreated] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
GO

enter image description here

Answer 1

查看sys.dm_exec_sessions以获取ASP.Net应用程序和SSMS会话。我猜测至少有一个SET设置不同。这可能导致不同的计划（最终这归因于参数嗅探），并且应用程序方面通常会因此而变得更糟。

有关详细信息，请参阅其他问题：

Stored procedure slow when called from web, fast from Management Studio

Procedure times out from ADO.NET but not in SSMS

Query times out when executed from web, but super-fast when executed from SSMS

ADO .NET vs. SQL Server Management Studio - ADO performs worse

另请阅读this great article by Erland Sommarskog。

Answer 2

也许这是一个糟糕的执行计划，通过一些非典型的SP调用创建。在执行SP或定义时尝试使用WITH RECOMPILE。

EXEC [dbo].[Report_Activity] @StartDate, @EndDate, @TotalActions WITH RECOMPILE

或

ALTER PROCEDURE [dbo].[Report_Activity]
    (
        @StartDate      DATETIME
    ,   @EndDate        DATETIME
    ,   @TotalActions INT OUTPUT
    )
WITH RECOMPILE
AS
...

您还可以运行sp_recompile来标记您的SP，以便在下次执行时进行重新编译。

SQL Server程序超时

2 个答案: