Performance Tuning with SQL Server Dynamic Management Views

• dbcc shrinkdatabase / shrinkfile
• dbcc indexdefrag / alter index reorganize
• transaction rollbacks.
Chapter 2: Connections, Sessions and Requests
• cpu_time – the total amount of processing time spent on this request
(in milliseconds)
• row_count – the number of rows that were processed for the request
• granted_query_memory – number of pages allocated to the execution of the
request; since this metric is measured in 8 KB pages, you'll need to convert accordingly;
I tend to want to review my metrics in MB, therefore I perform the following
conversion from pages to MB: MB = (Number of 8 KB Pages)/1024 * 8
• reads – total physical disk reads performed for this request
• writes – total physical writes performed for this request
• logical_reads – total number of reads from the data cache for this request.
Overview of sys.dm_exec_sql_text
Having retrieved the sql_handle from the sys.dm_exec_requests DMV (or any
other DMV that exposes it), we can then provide it as a parameter into the sys.dm_
exec_sql_text function, in order to retrieve the SQL text for a given batch/procedure.
The sys.dm_exec_sql_text table-valued function returns two columns that are only
interesting if the sql_handle refers to an object, such as a stored procedure, rather than
ad hoc SQL statements:
• dbid – the identifier (or surrogate key) for the database, if applicable; (note that this is
usually database_id in other objects)
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