35 lines
1.6 KiB
SQL
35 lines
1.6 KiB
SQL
-- +----------------------------------------------------------------------------+
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-- | Jeffrey M. Hunter |
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-- | jhunter@idevelopment.info |
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-- | www.idevelopment.info |
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-- |----------------------------------------------------------------------------|
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-- | Copyright (c) 1998-2011 Jeffrey M. Hunter. All rights reserved. |
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-- |----------------------------------------------------------------------------|
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-- | DATABASE : Oracle |
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-- | FILE : perf_lru_latch_contention.sql |
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-- | CLASS : Tuning |
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-- | PURPOSE : This script will detect latch contention in the db block buffer |
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-- | LRU. The ratio of sleeps/gets should be < 1%. |
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-- | NOTE : As with any code, ensure to test this script in a development |
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-- | environment before attempting to run it in production. |
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-- +----------------------------------------------------------------------------+
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SET LINESIZE 145
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SET PAGESIZE 9999
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SET VERIFY off
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COLUMN child_num HEADING "Child Number"
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COLUMN ratio_sleeps_gets HEADING "Sleeps / Gets Ratio"
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COLUMN ratio HEADING "Ratio"
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SELECT
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child# child_num
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, ROUND(sleeps/gets * 100,2) ratio_sleeps_gets
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, ROUND(((1 - sleeps/gets) * 100),2) ratio
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FROM
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v$latch_children
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WHERE
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name = 'cache buffers lru chain'
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/
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