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2589434ae0
Using pg_buffercache_summary() is significantly cheaper than querying pg_buffercache and summarizing in SQL. Author: Melih Mutlu <m.melihmutlu@gmail.com> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Aleksander Alekseev <aleksander@timescale.com> Reviewed-by: Zhang Mingli <zmlpostgres@gmail.com> Discussion: https://postgr.es/m/CAGPVpCQAXYo54Q%3D8gqBsS%3Du0uk9qhnnq4%2B710BtUhUisX1XGEg%40mail.gmail.com
25 lines
849 B
SQL
25 lines
849 B
SQL
CREATE EXTENSION pg_buffercache;
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select count(*) = (select setting::bigint
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from pg_settings
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where name = 'shared_buffers')
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from pg_buffercache;
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select buffers_used + buffers_unused > 0,
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buffers_dirty <= buffers_used,
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buffers_pinned <= buffers_used
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from pg_buffercache_summary();
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-- Check that the functions / views can't be accessed by default. To avoid
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-- having to create a dedicated user, use the pg_database_owner pseudo-role.
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SET ROLE pg_database_owner;
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SELECT * FROM pg_buffercache;
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SELECT * FROM pg_buffercache_pages() AS p (wrong int);
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SELECT * FROM pg_buffercache_summary();
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RESET role;
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-- Check that pg_monitor is allowed to query view / function
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SET ROLE pg_monitor;
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SELECT count(*) > 0 FROM pg_buffercache;
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SELECT buffers_used + buffers_unused > 0 FROM pg_buffercache_summary();
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