pgpg_prewarm用法

按照插件

> create extension pg_prewarm ;

缓存表

> test=# select pg_prewarm('weather','buffer' ) ; pg_prewarm > ------------ > 1

缓存表部分内容

test=# select pg_prewarm('weather','buffer','main',0,0) ; pg_prewarm ------------ 1 (1 row)

表大小只有0号页，只能缓存这么大

缓存索引

test=# \d+ weather Table "public.weather" Column | Type | Collation | Nullable | Default | Storage | Compression | Stats target | Description -----------+-----------------------+-----------+----------+---------+----------+-------------+--------------+------------- city | character varying(80) | | | | extended | | | temp_low | integer | | | | plain | | | temp_high | integer | | | | plain | | | prcp | real | | | | plain | | | date | date | | | | plain | | | Indexes: "idx_city" btree (city) Access method: heap test=# select pg_prewarm('idx_city','buffer' ) ; pg_prewarm ------------ 2

影响：