> ## 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.

# compact_parts_* MergeTree table settings

> ClickHouse MergeTree table settings in the compact_parts_* generated group.

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
  }}>Type</div>
      <div style={{
    overflowWrap: "anywhere"
  }}>{type}</div>
      <div style={{
    fontWeight: 600,
    opacity: 0.72,
    marginInlineStart: "0.5rem"
  }}>Default</div>
      <div style={{
    overflowWrap: "anywhere"
  }}>{default_value}</div>
      {changeable_without_restart && <div style={{
    fontWeight: 600,
    opacity: 0.72,
    marginInlineStart: "0.5rem"
  }}>
          Changeable without restart
        </div>}
      {changeable_without_restart && <div style={{
    overflowWrap: "anywhere"
  }}>
          {changeable_without_restart}
        </div>}
    </div>;
};

These settings are available in [system.merge\_tree\_settings](/docs/reference/system-tables/merge_tree_settings) and are autogenerated from ClickHouse source.

<h2 id="compact_parts_max_bytes_to_buffer">
  compact\_parts\_max\_bytes\_to\_buffer
</h2>

<SettingsInfoBlock type="UInt64" default_value="134217728" />

Only available in ClickHouse Cloud. Maximal number of bytes to write in a
single stripe in compact parts

<h2 id="compact_parts_max_granules_to_buffer">
  compact\_parts\_max\_granules\_to\_buffer
</h2>

<SettingsInfoBlock type="NonZeroUInt64" default_value="128" />

Only available in ClickHouse Cloud. Maximal number of granules to write in a
single stripe in compact parts

<h2 id="compact_parts_merge_max_bytes_to_prefetch_part">
  compact\_parts\_merge\_max\_bytes\_to\_prefetch\_part
</h2>

<SettingsInfoBlock type="UInt64" default_value="16777216" />

Only available in ClickHouse Cloud. Maximal size of compact part to read it
in a whole to memory during merge.