Take the 2-minute tour ×  I referred to this article:
sp_trace_setevent (Transact-SQL).  And trace my SQL Server on
production machine for months.  EventId of most of the traces
were: 10，12，14，17  The MSDN says:    • 10 RPC:Completed   • 12
SQL:BatchCompleted   • 14 Audit Login   • 17 ExistingConnection
Please tell me what do they mean in the performance perspective.
Which ones should I keep an eye on and examine in detail. Or am
I missing something. Thanks!  share|improve this question  2
Answers 2  up vote 4 down vote accepted  You appear to have
setup a trace with no understanding of why you've done so. There
is little point in running a trace for 10 minutes, let alone
months, without a reason.  Scenarios for using SQL Server
Profiler  The first step in using SQL Server Profiler is to
identify your reasons for monitoring an instance of SQL Server.
The most common scenarios (taken from the above link) which may
be relevant to you are:    • Find the worst-performing queries.
• Monitor stored procedure pe