"select a.relname as tablename,(a.relpages+CASE WHEN b.relpages is null THEN 0 ELSE b.relpages END+CASE WHEN c.relpages is null THEN 0 ELSE c.relpages END)*8 as size_in_K,a.relfilenode as \"OID\" from pg_class a left join pg_class b
"select case when count(*)=3 then 'TRUE' else 'FALSE' end from pg_settings where (name='stats_block_level' or name='stats_row_level' or name='stats_start_collector') and setting='on' ",
'Value must be TRUE to enable hit ratio statistics (<i>stats_start_collector</i>,<i>stats_row_level</i> and <i>stats_block_level</i> must be set to true in postgresql.conf)'),
'data cache hit ratio'=>array('RATIO',
"select case when blks_hit=0 then 0 else (1-blks_read::float/blks_hit)*100 end from pg_stat_database where datname='\$DATABASE'",
'=WarnCacheRatio'),
'IO',
'data reads'=>array('IO',
'select sum(heap_blks_read+toast_blks_read) from pg_statio_user_tables',
),
'data writes'=>array('IO',
'select sum(n_tup_ins/4.0+n_tup_upd/8.0+n_tup_del/4.0)/16 from pg_stat_user_tables',
'Count of inserts/updates/deletes * coef'),
'Data Cache',
'data cache buffers'=>array('DATAC',
"select setting from pg_settings where name='shared_buffers'",
'Number of cache buffers. <a href=http://www.varlena.com/GeneralBits/Tidbits/perf.html#basic>Tuning</a>'),
'cache blocksize'=>array('DATAC',
'select 8192',
'(estimate)'),
'data cache size'=>array('DATAC',
"select setting::integer*8192 from pg_settings where name='shared_buffers'",
''),
'operating system cache size'=>array('DATA',
"select setting::integer*8192 from pg_settings where name='effective_cache_size'",
'(effective cache size)'),
'Memory Usage',
'sort buffer size'=>array('CACHE',
"select setting::integer*1024 from pg_settings where name='sort_mem'",
'Size of sort buffer (per query)'),
'Connections',
'current connections'=>array('SESS',
'select count(*) from pg_stat_activity',
''),
'max connections'=>array('SESS',
"select setting from pg_settings where name='max_connections'",
''),
'Parameters',
'rollback buffers'=>array('COST',
"select setting from pg_settings where name='wal_buffers'",
'WAL buffers'),
'random page cost'=>array('COST',
"select setting from pg_settings where name='random_page_cost'",
'Cost of doing a seek (default=4). See <a href=http://www.varlena.com/GeneralBits/Tidbits/perf.html#less>random_page_cost</a>'),