STATISTICS VIEW · 统计视图

pg_stat_recovery_prefetch

The pg_stat_recovery_prefetch view will contain only one row. The columns wal_distance, block_distance and io_depth show current values, and the other columns show cumulative counters that can be reset with the pg_stat_reset_shared function.

首次收录 PG 15最近收录 PG 19当前字段 10

9.0 9.1 9.2 9.3 9.4 9.5 9.6 10 11 12 13 14 15 16 17 18 19^β3

已与 PostgreSQL 18.6 实例逐字段核对 · 原始实测记录 ↗

字段结构 PostgreSQL 18

pg_stat_recovery_prefetch

字段 / COLUMN	类型 / TYPE	说明 / DESCRIPTION
`stats_reset`	`timestamp with time zone`	Time at which these statistics were last reset
`prefetch`	`bigint`	Number of blocks prefetched because they were not in the buffer pool
`hit`	`bigint`	Number of blocks not prefetched because they were already in the buffer pool
`skip_init`	`bigint`	Number of blocks not prefetched because they would be zero-initialized
`skip_new`	`bigint`	Number of blocks not prefetched because they didn't exist yet
`skip_fpw`	`bigint`	Number of blocks not prefetched because a full page image was included in the WAL
`skip_rep`	`bigint`	Number of blocks not prefetched because they were already recently prefetched
`wal_distance`	`integer`文档原写法：`int`	How many bytes ahead the prefetcher is looking
`block_distance`	`integer`文档原写法：`int`	How many blocks ahead the prefetcher is looking
`io_depth`	`integer`文档原写法：`int`	How many prefetches have been initiated but are not yet known to have completed

标记“隐式列”的字段不包含在 SELECT * 中；部分早期统计视图由同版本源码补全，额外来源会显示在字段说明中。

字段演化矩阵

悬停查看字段类型

存在新增 / 类型或属性变化移除

字段 / COLUMN	9.0	9.1	9.2	9.3	9.4	9.5	9.6	10	11	12	13	14
`stats_reset`	–	–	–	–	–	–	–	–	–	–	–	–
`prefetch`	–	–	–	–	–	–	–	–	–	–	–	–
`hit`	–	–	–	–	–	–	–	–	–	–	–	–
`skip_init`	–	–	–	–	–	–	–	–	–	–	–	–
`skip_new`	–	–	–	–	–	–	–	–	–	–	–	–
`skip_fpw`	–	–	–	–	–	–	–	–	–	–	–	–
`skip_rep`	–	–	–	–	–	–	–	–	–	–	–	–
`wal_distance`	–	–	–	–	–	–	–	–	–	–	–	–
`block_distance`	–	–	–	–	–	–	–	–	–	–	–	–
`io_depth`	–	–	–	–	–	–	–	–	–	–	–	–

9.0 是收录基线；基线中已存在的字段不标记为新增。矩阵按字段名称对齐，重命名显示为旧字段移除与新字段新增。

演化时间线

相邻大版本的变化

PostgreSQL 15 ← 14新增目录

+ stats_reset+ prefetch+ hit+ skip_init+ skip_new+ skip_fpw+ skip_rep+ wal_distance+ block_distance+ io_depth

比较任意两个版本

起始版本 / FROM目标版本 / TO包含描述更新

选择两个版本，查看字段的新增、移除与类型变化。交互比较需要 JavaScript；演化时间线可直接阅读。