---
title: ''
description: Telegraf plugin for collecting metrics from Device Mapper Cache
url: https://docs.influxdata.com/telegraf/v1/input-plugins/dmcache/
estimated_tokens: 481
product: Telegraf Controller
version: v1
publisher: InfluxData
canonical: https://docs.influxdata.com/telegraf/v1/input-plugins/dmcache/
date: '2026-05-21T20:10:18+02:00'
lastmod: '2026-05-21T20:10:18+02:00'
---

==========

* Telegraf v1.3.0+

[Plugin source](https://github.com/influxdata/telegraf/tree/v1.39.0/plugins/inputs/dmcache/)[Download configuration](https://raw.githubusercontent.com/influxdata/telegraf/refs/tags/v1.39.0/plugins/inputs/dmcache/sample.conf)

# Device Mapper Cache Input Plugin

This plugin provide a native collection for dmsetup based statistics for[dm-cache](https://docs.kernel.org/admin-guide/device-mapper/cache.html).

> [!Note]
> This plugin requires super-user permissions! Please make sure, Telegraf is
> able to run `sudo /sbin/dmsetup status --target cache` without requiring a
> password.

**Introduced in:** Telegraf v1.3.0**Tags:** system**OS support:** linux

## Global configuration options

Plugins support additional global and plugin configuration settings for tasks
such as modifying metrics, tags, and fields, creating aliases, and configuring
plugin ordering. See [CONFIGURATION.md](/telegraf/v1/configuration/#plugins) for more details.

## Configuration

```toml
# Provide a native collection for dmsetup based statistics for dm-cache
# This plugin ONLY supports Linux
[[inputs.dmcache]]
  ## Whether to report per-device stats or not
  per_device = true
```

## Metrics

* dmcache
  * length
  * target
  * metadata\_blocksize
  * metadata\_used
  * metadata\_total
  * cache\_blocksize
  * cache\_used
  * cache\_total
  * read\_hits
  * read\_misses
  * write\_hits
  * write\_misses
  * demotions
  * promotions
  * dirty

## Tags

* All measurements have the following tags:
  * device

## Example Output

```text
dmcache,device=example cache_blocksize=0i,read_hits=995134034411520i,read_misses=916807089127424i,write_hits=195107267543040i,metadata_used=12861440i,write_misses=563725346013184i,promotions=3265223720960i,dirty=0i,metadata_blocksize=0i,cache_used=1099511627776ii,cache_total=0i,length=0i,metadata_total=1073741824i,demotions=3265223720960i 1491482035000000000
```