Friday, December 24, 2010

Server Side trace

Most of us are aware of tracing queries using SQL profiler. But an effective way of performing tracing is using a server side trace.

Whats special about server side trace?

1) Server Side trace uses much less resources than SQL Profiler.

2) Server side trace runs within the server which means the dependency on client tool is removed.In other words, when you run a profiler from a client machine, once you close the profiler, the SQL trace on the server stops. for ex: if the DBA is running a trace on production server from his desktop, then if the DBA's machine is restarted then the trace automatically stops. With a Server side trace as long as server is up the trace will be running and it doesnt depend on any client machine or tool.

3) SQL Profiler tool, while running, consumes lots of space on the C: drive ( or on the drive executables are installed ) by writing temporary files to C:\...\..\ temp folder. Temporoary files are cleared only by stopping the profiler, which would mean stopping the trace. There are enough articles on the net for Server Side traces. Please refer here and here. These links provide a fairly comprehensive expalantion on server side traces.

In short they say

1) configure the trace using profiler

2) Use the File and Export option on SQL Profiler to export the script of the trace.

3) Make the change on sp_trace_create parameter to 2 so that files roll over after the first trace file is filled up. If not the trace stops after the first trc file is full.

4) Execute it from SSMS to get the server side trace started.

5) Use the following functions to administer the trace

1) fn_trace_getinfo(default) or select * from sys.traces - to check trace status
2) sp_trace_setstatus - To start, stop and close a thread
3) fn_trace_gettable - To get the results of the trace files into a table.

Wednesday, December 8, 2010

Perfmon counters list - Quest poster

Stumbled upon this PDF from quest which lists the important Perfmon counters and their acceptable values. A must print and stick poster which can be very very handy indeed. Saves so much of time and effort involved in reading pages of documents to know the important counters and correct value for each of them. Superb stuff. Thanks Quest !!!