dbcc-sqlperf-transact-sql.md

title	DBCC SQLPERF (Transact-SQL) | Microsoft Docs
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ms.date	01/07/2018
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f1_keywords	SQLPERF DBCC_SQLPERF_TSQL SQLPERF_TSQL DBCC SQLPERF
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DBCC SQLPERF (Transact-SQL)

[!INCLUDEtsql-appliesto-ss2008-xxxx-xxxx-xxx-md]

Provides transaction log space usage statistics for all databases. In [!INCLUDEssNoVersion] it can also be used to reset wait and latch statistics.

Applies to: [!INCLUDEssNoVersion] ([!INCLUDEssKatmai] through [!INCLUDEssCurrent]), [!INCLUDEsqldbesa] (Preview in some regions)

Transact-SQL Syntax Conventions

Syntax

DBCC SQLPERF   
(  
     [ LOGSPACE ]  
     | [ "sys.dm_os_latch_stats" , CLEAR ]  
     | [ "sys.dm_os_wait_stats" , CLEAR ]  
)   
     [WITH NO_INFOMSGS ]  

Arguments

LOGSPACE
Returns the current size of the transaction log and the percentage of log space used for each database. You can use this information to monitor the amount of space used in a transaction log.

Important

Starting with [!INCLUDEssSQL11], use sys.dm_db_log_space_usage instead of LOGSPACE, to return space usage information for the transaction log per database.

"sys.dm_os_latch_stats", CLEAR
Resets the latch statistics. For more information, see sys.dm_os_latch_stats (Transact-SQL). This option is not available in [!INCLUDEssSDS].

"sys.dm_os_wait_stats", CLEAR
Resets the wait statistics. For more information, see sys.dm_os_wait_stats (Transact-SQL). This option is not available in [!INCLUDEssSDS].

WITH NO_INFOMSGS
Suppresses all informational messages that have severity levels from 0 through 10.

Result Sets

The following table describes the columns in the result set.

Column name	Definition
Database Name	Name of the database for the log statistics displayed.
Log Size (MB)	Current size allocated to the log. This value is always smaller than the amount originally allocated for log space because the [!INCLUDEssDE] reserves a small amount of disk space for internal header information.
Log Space Used (%)	Percentage of the log file currently in use to store transaction log information.
Status	Status of the log file. Always 0.

Remarks

The transaction log records each transaction made in a database. For more information see The Transaction Log (SQL Server) and SQL Server Transaction Log Architecture and Management Guide.

Permissions

On [!INCLUDEssNoVersion] to run DBCC SQLPERF(LOGSPACE) requires VIEW SERVER STATE permission on the server. To reset wait and latch statistics requires ALTER SERVER STATE permission on the server.

On [!INCLUDEssSDS] Premium Tiers requires the VIEW DATABASE STATE permission in the database. On [!INCLUDEssSDS] Standard and Basic Tiers requires the [!INCLUDEssSDS] admin account. Reset wait and latch statistics are not supported.

Examples

A. Displaying log space information for all databases

The following example displays LOGSPACE information for all databases contained in the instance of [!INCLUDEssNoVersion].

DBCC SQLPERF(LOGSPACE);  
GO  

[!INCLUDEssResult]

Database Name Log Size (MB) Log Space Used (%) Status        
------------- ------------- ------------------ -----------   
master         3.99219      14.3469            0   
tempdb         1.99219      1.64216            0   
model          1.0          12.7953            0   
msdb           3.99219      17.0132            0   
AdventureWorks 19.554688    17.748701          0  

B. Resetting wait statistics

The following example resets the wait statistics for the instance of [!INCLUDEssNoVersion].

DBCC SQLPERF("sys.dm_os_wait_stats",CLEAR);  

See Also

DBCC (Transact-SQL)
sys.dm_os_latch_stats (Transact-SQL)
sys.dm_os_wait_stats (Transact-SQL)
sp_spaceused (Transact-SQL)
sys.dm_db_log_info (Transact-SQL)
sys.dm_db_log_space_usage (Transact-SQL)
sys.dm_db_log_stats (Transact-SQL)