| 类型: | real |
| 默认: | 2 (2ms) |
| 最低限度: | -1 (-1) |
| 最大: | 100 (100ms) |
| 单元: | milliseconds (ms) |
| 上下文: | sighup |
| 重新开始: | false |
指定用于自动VACUUM操作中的代价延迟值。如果指定-1（默认值），则使用vacuum_cost_delay值。 如果指定值时没有单位，则以毫秒为单位。默认值为2毫秒。该参数只能在postgresql.conf文件或在服务器命令中设置。但是对个别表可以通过修改表存储参数来覆盖该设置。
建议 [EN]
If autovacuum is having too much of a performance impact on running queries, you might want to increase this setting to 50ms. However, this will also cause individual vacuum tasks to take longer.