Trace Flag Basics

Erin Stellato explains the basics behind trace flags in SQL Server:

Trace flag 1118 addresses contention that can exist on a particular type of page in a database, the SGAM page.  This trace flag typically provides benefit for customers that make heavy use of the tempdb system database.  In SQL Server 2016, you change this behavior using the MIXED_PAGE_ALLOCATION database option, and there is no need for TF 1118.

Trace flag 3023 is used to enable the CHECKSUM option, by default, for all backups taken on an instance.  With this option enabled, page checksums are validated during a backup, and a checksum for the entire backup is generated.  Starting in SQL Server 2014, this option can be set instance-wide through sp_configure (‘backup checksum default’).

The last trace flag, 3226, prevents the writing of successful backup messages to the SQL Server ERRORLOG.  Information about successful backups is still written to msdb and can be queried using T-SQL.  For servers with multiple databases and regular transaction log backups, enabling this option means the ERRORLOG is no longer bloated with BACKUP DATABASE and Database backed up messages.  As a DBA, this is a good thing because when I look in my ERRORLOG, I really only want to see errors, I don’t want to scroll through hundreds or thousands of entries about successful backups.

Click through for more useful information, including a list of officially supported trace flags.

Related Posts

Enabling Large Memory Pages in SQL Server

David Klee talks us through large memory pages: SQL Server Enterprise Edition can leverage large memory pages to reduce the amount of memory pointers required for larger SQL Server deployments. Reducing the number of pointers makes the database engine more efficient, especially for SQL Servers with greater than 32GB of RAM. A normal memory block […]

Read More

Straight Talk On Trace Flags

Pam Lahoud explains the purpose of trace flags and talks about a very important trace flag, 4199: Some trace flags are used to enable enhanced debugging features such as additional logging, memory dumps etc. and are used only when you are working with Microsoft Support to provide additional data for troubleshooting. These trace flags are not ones […]

Read More

Categories

March 2017
MTWTFSS
« Feb Apr »
 12345
6789101112
13141516171819
20212223242526
2728293031