Logging provides very useful troubleshooting data, but significantly degrades system performance. You can use the SMS Service Manager to enable or disable tracing for each SMS service. If you enable logging, you should also use the SMS Service Manager to set the trace file log size. Be sure the file is large enough to collect at least 24 hours worth of data in each log file.
SMS allows you to enable logging for SQL Server as well as for the SMS services. To enable SMS logging for SQL Server, use the following registry key to change the values for SQLEnabled and Enabled from 0 to 1:
HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\SMS\TRACING
You must restart all SMS services and tools for this change to take effect. SQL Server logging is extremely resource-intensive. In general, you should not enable SQL Server logging unless you are actively working on a SQL Server problem.