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

# pmdasummary(1)

summary performance metrics domain agent (PMDA)

## NAME

**pmdasummary** - summary performance metrics domain agent (PMDA)

## SYNOPSIS

**$PCP\_PMDAS\_DIR/summary/pmdasummary** \[**-D** *debug*\] \[**-d** *domain*\] \[**-h** *helpfile*\] \[**-l** *logfile*\] \[**-U** *username*\] *pmie-command-line*

## DESCRIPTION

**pmdasummary** is a Performance Metrics Domain Agent (PMDA) which derives performance metrics values from values made available by other PMDAs. **pmdasummary** consists of two processes:

- **pmie process**

  The inference engine for performance values [**pmie**(1)](/pmie/1.md) is used to periodically sample values for the base metrics and compute the derived values. This process is launched with the given *pmie-command-line* arguments by the main process, described below.

- **main process**

  The main process reads and buffers the values computed by [**pmie**(1)](/pmie/1.md) and makes them available to the performance metrics collector daemon [**pmcd**(1)](/pmcd/1.md).

A brief description of the **pmdasummary** 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.

- **-h**

  This option specifies an alternative help text file *helpfile* for describing the metrics that **pmdasummary** represents.

- **-l**

  Location of the log file.  By default, a log file named *summary.log* is written in the current directory of [**pmcd**(1)](/pmcd/1.md) when **pmdasummary** 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.

- **-U**

  User account under which to run the agent. The default is the unprivileged "pcp" account in current versions of PCP, but in older versions the superuser account ("root") was used by default.

## INSTALLATION

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

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

If you want to undo the installation, do the following as root:

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

**pmdasummary** 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 **pmdasummary**

- **$PCP\_PMDAS\_DIR/summary/expr.pmie**

  default [**pmie**(1)](/pmie/1.md) expressions defining the summary metrics

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

  default help text for the summary metrics

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

  installation script for the **pmdasummary** agent

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

  undo installation script for the **pmdasummary** agent

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

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

## 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.

## SEE ALSO

[**PCPIntro**(1)](/PCPIntro/1.md), [**pmcd**(1)](/pmcd/1.md) and [**pmie**(1)](/pmie/1.md).