---
name: "pmdadocker"
section: "1"
platform: "linux"
package: "pcp"
version: "7.2.2-2"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/pmdadocker"
---

# pmdadocker(1)

docker performance metrics domain agent (PMDA)

## NAME

**pmdadocker** - docker performance metrics domain agent (PMDA)

## SYNOPSIS

**$PCP\_PMDAS\_DIR/docker/pmdadocker** \[**-D** *debug*\] \[**-d** *domain*\] \[**-l** *logfile*\]

## DESCRIPTION

**pmdadocker** is a docker Performance Metrics Domain Agent (PMDA) which exposes performance metrics as reported from the Docker Remote API.

A brief description of the **pmdadocker** command line options follows:

- **-d**

  It is absolutely crucial that the performance metrics *domain* number specified here is unique and consistent. That is, *domain* should be different for every PMDA on the one host, and the same *domain* number should be used for the same PMDA on all hosts.

- **-l**

  Location of the log file.  By default, a log file named *docker.log* is written in the current directory of [**pmcd**(1)](/pmcd/1.md) when **pmdadocker** is started, i.e. **$PCP\_LOG\_DIR/pmcd**. If the log file cannot be created or is not writable, output is written to the standard error instead.

Remote API metric requests are activated automatically and are fetched on a timer.  This timer is represented as a by **pmdadocker** via the **docker.control.timing.** By default, **pmdadocker** will be set to fetch on a 1 second interval.

**pmdadocker** will iterate over three different **docker** remote API calls:

- **/containers/$ID/json**

  Container metrics regarding the current state of the container. Such as PID, name or if the container is running.

- **/version**

  Basic version metrics about the current docker daemon in use.

- **/containers/$ID/stats?stream=0**

  More in depth memory and cpu metrics of the container.

## INSTALLATION

If you want access to the names, help text and values for the docker performance metrics, do the following as root:

```
# cd $PCP_PMDAS_DIR/docker
# ./Install
```

If you want to undo the installation (and remove both PMDAs), do the following as root:

```
# cd $PCP_PMDAS_DIR/docker
# ./Remove
```

**pmdadocker** is launched by [**pmcd**(1)](/pmcd/1.md) and should never be executed directly. The Install and Remove scripts notify [**pmcd**(1)](/pmcd/1.md) when the agent is installed or removed.

## FILES

- **$PCP\_PMCDCONF\_PATH**

  command line options used to launch **pmdadocker**

- **$PCP\_PMDAS\_DIR/docker/help**

  default help text file for the docker metrics

- **$PCP\_PMDAS\_DIR/docker/Install**

  installation script for the **pmdadocker** agent

- **$PCP\_PMDAS\_DIR/docker/Remove**

  undo installation script for the **pmdadocker** agent

- **$PCP\_LOG\_DIR/pmcd/docker.log**

  default log file for error messages and other information from **pmdadocker**

## PCP ENVIRONMENT

Environment variables with the prefix **PCP\_** are used to parameterize the file and directory names used by PCP. On each installation, the file **/etc/pcp.conf** contains the local values for these variables. The **$PCP\_CONF** variable may be used to specify an alternative configuration file, as described in [**pcp.conf**(5)](/pcp.conf/5.md).

## DEBUGGING OPTIONS

The **-D** or **--debug** option enables the output of additional diagnostics on *stderr* to help triage problems, although the information is sometimes cryptic and primarily intended to provide guidance for developers rather than for end-users. *debug* is a comma separated list of debugging options; use [**pmdbg**(1)](/pmdbg/1.md) with the **-l** option to obtain a list of the available debugging options and their meaning.

Debugging options specific to **pmdadocker** are as follows:

| | |
| --- | --- |
| Option | Description |
| appl1 | report failure to fetch stats via http |

## SEE ALSO

[**PCPIntro**(1)](/PCPIntro/1.md), [**pmcd**(1)](/pmcd/1.md), [**pcp.conf**(5)](/pcp.conf/5.md), [**pcp.env**(5)](/pcp.env/5.md) and [**docker**(1)](/docker/1.md).