Performance Tuning with SQL Server Dynamic Management Views

WHERE cntr_type = @PERF_COUNTER_LARGE_RAWCOUNT
AND object_name = @object_name
AND counter_name IN ( 'Log Growths', 'Log Shrinks' )
AND cntr_value > 0
ORDER BY object_name ,
counter_name ,
instance_name
Listing 7.8: Monitoring changes in the size of the transaction log.
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Chapter 7: OS and Hardware Interaction
Log size adjustments aren't problematical in all cases but it is quite costly to have users on
a busy server waiting while space is being allocated to the log, and an excessive number
of small auto-grow events will fragment the log. Shrinking the log (i.e. removing any
unused space) is, as a general habit, a bad idea as it just means that you are likely to see a
log growth event very soon. The best practice is to have log space pre-allocated and not to
adjust it; free log space is not harmful to performance, but a full log is.
Deprecated feature use
In 2008, a new set of counters was added to show deprecated feature utilization. You can
get to them using a query of the form shown in Listing 7.9. In cases where you've recently
upgraded a system, it's useful to know what deprecated features are still being used, so
that you can plan on updating them, to avoid having them fail when you are upgrading
again in a few years.
DECLARE @object_name SYSNAME
SET @object_name = CASE WHEN @@servicename = 'MSSQLSERVER' THEN 'SQLServer'
ELSE 'MSSQL$' + @@serviceName
END + ':Deprecated Features'
DECLARE @PERF_COUNTER_LARGE_RAWCOUNT INT
SELECT @PERF_COUNTER_LARGE_RAWCOUNT = 65792
SELECT object_name ,
counter_name ,
instance_name ,
cntr_value