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buzzi
Starting Member
48 Posts |
Posted - 2008-10-21 : 11:10:58
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Hi all,I need experts help in explaining the below query that i got when going through the documentation of tempdb,the below query will return the top 10 I/O intensive queries, that are causing my tempdb to bloat like crazy.SELECT top 10 (total_logical_reads/execution_count), (total_logical_writes/execution_count), (total_physical_reads/execution_count), Execution_count, sql_handle, plan_handleFROM sys.dm_exec_query_stats ORDER BY (total_logical_reads + total_logical_writes) DescWhen i ran this on my production server, I have the first record coming as logicalreads logicalwrites physicalreads Execution_count3646472 85 25990 140Q1. I got the sp that is running, and turned on the profiler to see the reads column, I am confused to see this very low, some times few 100's and other times few 1000's, which is in contrary of the logical reads(3646472), that i see in the above record.I am not able to make sense of this, can somebody please explain whats going on?Q2.does not droping a temp table explicitly creates any problem, i know the temp tables gets dropped when the user session is closed,but is there any downside of keeping this till the user section ends?Thanks for all your help |
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buzzi
Starting Member
48 Posts |
Posted - 2008-10-21 : 15:00:56
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Hi all, any insight into this will be of great helpThank you all |
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sodeep
Master Smack Fu Yak Hacker
7174 Posts |
Posted - 2008-10-21 : 15:10:15
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quote: Originally posted by buzzi Hi all,I need experts help in explaining the below query that i got when going through the documentation of tempdb,the below query will return the top 10 I/O intensive queries, that are causing my tempdb to bloat like crazy.SELECT top 10 (total_logical_reads/execution_count), (total_logical_writes/execution_count), (total_physical_reads/execution_count), Execution_count, sql_handle, plan_handleFROM sys.dm_exec_query_stats ORDER BY (total_logical_reads + total_logical_writes) DescWhen i ran this on my production server, I have the first record coming as logicalreads logicalwrites physicalreads Execution_count3646472 85 25990 140Q1. I got the sp that is running, and turned on the profiler to see the reads column, I am confused to see this very low, some times few 100's and other times few 1000's, which is in contrary of the logical reads(3646472), that i see in the above record.I am not able to make sense of this, can somebody please explain whats going on?I guess you wanna look physical read.Q2.does not droping a temp table explicitly creates any problem, i know the temp tables gets dropped when the user session is closed,but is there any downside of keeping this till the user section ends?Depends on what temp table or table variable is doing.If you inserting millions of records to it,then TempDB will increase.It is good idea to drop temp table .Thanks for all your help
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buzzi
Starting Member
48 Posts |
Posted - 2008-10-21 : 23:25:17
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Thank You sodeep, ok i took your suggestion for the 2nd point and got this right, but on the 1st one can you please eloborate |
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