> ## Documentation Index
> Fetch the complete documentation index at: https://clickhouse.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# async_insert_* 会话设置

> 按 async_insert_* 分组生成的 ClickHouse 会话设置。

export const SettingsInfoBlock = ({type, default_value, changeable_without_restart}) => {
  return <div className="not-prose" style={{
    display: "flex",
    flexWrap: "wrap",
    alignItems: "baseline",
    columnGap: "0.5rem",
    rowGap: "0.125rem",
    margin: "0.375rem 0",
    fontSize: "0.8125rem",
    lineHeight: "1.125rem"
  }}>
      <div style={{
    fontWeight: 600,
    opacity: 0.72
  }}>类型</div>
      <div style={{
    overflowWrap: "anywhere"
  }}>{type}</div>
      <div style={{
    fontWeight: 600,
    opacity: 0.72,
    marginInlineStart: "0.5rem"
  }}>默认值</div>
      <div style={{
    overflowWrap: "anywhere"
  }}>{default_value}</div>
      {changeable_without_restart && <div style={{
    fontWeight: 600,
    opacity: 0.72,
    marginInlineStart: "0.5rem"
  }}>
          无需重启即可更改
        </div>}
      {changeable_without_restart && <div style={{
    overflowWrap: "anywhere"
  }}>
          {changeable_without_restart}
        </div>}
    </div>;
};

这些设置可在 [system.settings](/docs/zh/reference/system-tables/settings) 中查看，并根据 [源代码](https://github.com/ClickHouse/ClickHouse/blob/master/src/Core/Settings.cpp) 自动生成。

<div id="async_insert">
  ## async\_insert
</div>

<SettingsInfoBlock type="Bool" default_value="1" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "26.2"},{"label": "1"},{"label": "默认启用异步插入。"}]}]} />

如果为 true，来自 INSERT 查询的数据会先存储在队列中，随后在后台刷写到表中。如果 wait\_for\_async\_insert 为 false，则 INSERT 查询几乎会立即处理；否则客户端会等待，直到数据刷写到表中

<div id="async_insert_busy_timeout_decrease_rate">
  ## async\_insert\_busy\_timeout\_decrease\_rate
</div>

<SettingsInfoBlock type="Double" default_value="0.2" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "24.2"},{"label": "0.2"},{"label": "自适应异步插入超时按指数速率下降的速率"}]}]} />

自适应异步插入超时按指数速率下降的速率

<div id="async_insert_busy_timeout_increase_rate">
  ## async\_insert\_busy\_timeout\_increase\_rate
</div>

<SettingsInfoBlock type="Double" default_value="0.2" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "24.2"},{"label": "0.2"},{"label": "自适应异步插入超时增大的指数增长率"}]}]} />

自适应异步插入超时增大的指数增长率

<div id="async_insert_busy_timeout_max_ms">
  ## async\_insert\_busy\_timeout\_max\_ms
</div>

**别名**: `async_insert_busy_timeout_ms`

<SettingsInfoBlock type="毫秒" default_value="200" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "24.2"},{"label": "200"},{"label": "异步插入超时的最小值（以毫秒为单位）；async_insert_busy_timeout_ms 是 async_insert_busy_timeout_max_ms 的别名"}]}]} />

从首条数据出现开始，每个查询在转储已收集的数据前的最长等待时间。

Cloud 默认值：`1000` (1 秒) 。

<div id="async_insert_busy_timeout_min_ms">
  ## async\_insert\_busy\_timeout\_min\_ms
</div>

<SettingsInfoBlock type="毫秒" default_value="50" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "24.2"},{"label": "50"},{"label": "异步插入超时的最小值（以毫秒计）；它也用作初始值，后续可能会由自适应算法调大"}]}]} />

如果通过 async\_insert\_use\_adaptive\_busy\_timeout 启用了自动调整，则该值表示自首次出现数据起，每个查询在转储已收集数据之前的最短等待时间。它也用作自适应算法的初始值

<div id="async_insert_deduplicate">
  ## async\_insert\_deduplicate
</div>

<SettingsInfoBlock type="Bool" default_value="0" />

对于复制表中的异步 INSERT 查询，指定是否对插入块进行去重

<div id="async_insert_max_data_size">
  ## async\_insert\_max\_data\_size
</div>

<SettingsInfoBlock type="UInt64" default_value="10485760" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "24.2"},{"label": "10485760"},{"label": "之前的值似乎过小。"}]}]} />

每个查询在插入前可收集的未解析数据的最大字节数

Cloud 默认值：`104857600` (100 MiB) 。

<div id="async_insert_max_query_number">
  ## async\_insert\_max\_query\_number
</div>

<SettingsInfoBlock type="UInt64" default_value="450" />

实际写入前允许的最大 insert 查询数。
仅当设置 [`async_insert_deduplicate`](/docs/zh/reference/settings/session-settings/async-insert#async_insert_deduplicate) 为 1 时才生效。

<div id="async_insert_poll_timeout_ms">
  ## async\_insert\_poll\_timeout\_ms
</div>

<SettingsInfoBlock type="毫秒" default_value="10" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "24.2"},{"label": "10"},{"label": "从异步插入队列轮询数据的超时时间（毫秒）"}]}]} />

从异步插入队列轮询数据的超时时间

<div id="async_insert_use_adaptive_busy_timeout">
  ## async\_insert\_use\_adaptive\_busy\_timeout
</div>

<SettingsInfoBlock type="Bool" default_value="1" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "24.2"},{"label": "1"},{"label": "使用自适应异步插入超时"}]}]} />

如果设置为 true，则异步插入将使用自适应忙碌超时