SQL Server exposes multiple trace flags which are required to set specific server characteristics or to switch off a particular behavior. Some trace flags are required to enable the fix post the installation of the update.
This is currently a work-in-progress. The trace flags mentioned in the table below have the associated public article links mentioned which provide more information about the trace flag.
If you want a trace flag to be mentioned in the list below, then feel free to leave a comment. Note that only publicly documented trace flags will appear in this list.
Disclaimer
1. Data mentioned below is as of 29th June 2012.
2. Trace flags should be used under the guidance of Microsoft SQL Server support. They are used in this post for discussion purposes only and may not be supported in future versions.
3. Trace flags for hotfixes should be only enabled if the fix is applicable to the SQL Server instance that you are enabling the trace flag on.
TroubleshootingSQL 