﻿---
title: Indexing buffer settings
description: The indexing buffer is used to store newly indexed documents. When it fills up, the documents in the buffer are written to a segment on disk. It is divided...
url: https://www.elastic.co/elastic/docs-builder/docs/2509/reference/elasticsearch/configuration-reference/indexing-buffer-settings
applies_to:
  - Self-managed Elastic deployments: Generally available in 9.0+
---

# Indexing buffer settings
The indexing buffer is used to store newly indexed documents. When it fills up, the documents in the buffer are written to a segment on disk. It is divided between all shards on the node.
The following settings are *static* and must be configured on every data node in the cluster:
<definitions>
  <definition term="indices.memory.index_buffer_size">
    ([Static](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/2509/deploy-manage/stack-settings#static-cluster-setting)) Accepts either a percentage or a byte size value. It defaults to `10%`, meaning that `10%` of the total heap allocated to a node will be used as the indexing buffer size shared across all shards.
  </definition>
  <definition term="indices.memory.min_index_buffer_size">
    ([Static](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/2509/deploy-manage/stack-settings#static-cluster-setting)) If the `index_buffer_size` is specified as a percentage, then this setting can be used to specify an absolute minimum. Defaults to `48mb`.
  </definition>
  <definition term="indices.memory.max_index_buffer_size">
    ([Static](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/2509/deploy-manage/stack-settings#static-cluster-setting)) If the `index_buffer_size` is specified as a percentage, then this setting can be used to specify an absolute maximum. Defaults to unbounded.
  </definition>
</definitions>