1/23/2024 0 Comments Microsoft docs trace flag 3226![]() ![]() Using –T with the trace flag as a startup parameter for the SQL Server serviceĮnabling a trace flag with DBCC TRACEON is done using T-SQL, and you have the option to set the trace flag at the session or global level.If you find you do want to give a trace flag try, there are two ways to enable/disable them: Notice I say “try” because even with all your testing, if may not be the right solution for your environment. Finally, after it’s gone through rigorous testing, you can try it in production. If you believe you should enable a trace flag, enable it in a test or development environment first where you can recreate the problem, and then test it thoroughly. In all cases, it’s important to first confirm that what you’re seeing in your environment matches the behavior described by the trace flag. You may have it recommended to you by a consultant, or another DBA or developer. You could also attend a user group meeting, a SQLSaturday or conference session, and hear the same thing. ![]() How will you know if you should use a trace flag? Online you’ll typically come across a forum post, blog post, or article that describes a scenario that you might be having, with the recommendation that you fix it with a trace flag. If you ever use an undocumented trace flag and you have a problem, Microsoft will not provide support for that problem if you decide to use an undocumented trace flag, tread carefully, particularly in production. An undocumented trace flag is one that is not supported by Microsoft. You can find a list of supported trace flags on MSDN, and as I alluded to initially, there are undocumented trace flags. 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. 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. Information about successful backups is still written to msdb and can be queried using T-SQL. The last trace flag, 3226, prevents the writing of successful backup messages to the SQL Server ERRORLOG. Starting in SQL Server 2014, this option can be set instance-wide through sp_configure (‘ backup checksum default’). With this option enabled, page checksums are validated during a backup, and a checksum for the entire backup is generated. Trace flag 3023 is used to enable the CHECKSUM option, by default, for all backups taken on an instance. In SQL Server 2016, you change this behavior using the MIXED_PAGE_ALLOCATION database option, and there is no need for TF 1118. This trace flag typically provides benefit for customers that make heavy use of the tempdb system database. ![]() Trace flag 1118 addresses contention that can exist on a particular type of page in a database, the SGAM page. 3023 (for versions prior to SQL Server 2014).1118 (for versions prior to SQL Server 2016).There are only three (3) trace flags that we at SQLskills recommend, by default, for a SQL Server installation: This isn’t always possible, which is why there’s always a slight risk with trace flags. The number one recommendation I always make when someone asks about using a trace flag is to test it, ideally in an identical or comparable situation. As such, trace flags in SQL Server are something to use with caution. In some cases, it can adversely affect the problem you’re trying to fix, or create a different issue. A trace flag is ideally used for improvement, but there can be situations where a trace flag doesn’t provide the intended benefit. SQL Server trace flags are used to change the behavior of the engine in some way. If you’ve never used a trace flag, you might wonder why you might need one, and how you would know if you did need it. If you’re new to SQL Server, you might have heard or read some of the above statements. “We fixed the problem using an undocumented trace flag.” “You should always use trace flag X for a SQL Server install.” ![]()
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