PMDADARWIN(1)

NAME
pmdadarwin - Darwin (macOS) kernel PMDA

SYNOPSIS
$PCP_PMDAS_DIR/darwin/pmdadarwin [-d domain] [-l logfile] [-U username]

DESCRIPTION
pmdadarwin is a Performance Metrics Domain Agent (PMDA) which extracts performance metrics from the macOS (Darwin) kernel.

The darwin PMDA exports metrics that examine memory utilization, virtual memory statistics, network interface statistics, disk I/O statistics, TCP connection states, and various protocol statistics including TCP, UDP, and ICMP.

TCP STATISTICS CONFIGURATION
On macOS, access to detailed TCP protocol statistics is controlled by the kernel sysctl parameter net.inet.tcp.disable_access_to_stats. By default, this is set to 1 (disabled) for privacy and security.

When disabled, all network.tcp.* metrics (except connection state counts from network.tcpconn.*) will report zero values. The PMDA will log a warning message on startup if TCP statistics access is detected to be disabled.

  Manual Configuration
To enable TCP statistics manually, run as root:

$ sudo sysctl -w net.inet.tcp.disable_access_to_stats=0

To make this permanent across reboots, add to /etc/sysctl.conf:

net.inet.tcp.disable_access_to_stats=0

Note: This setting is not protected by System Integrity Protection (SIP) and can be modified as root.

INSTALLATION
The darwin PMDA is installed and available by default on macOS systems. If you want to undo the installation, do the following as root:

# cd $PCP_PMDAS_DIR/darwin
# ./Remove

If you want to enable the PMDA again, do the following as root:

# cd $PCP_PMDAS_DIR/darwin
# ./Install

pmdadarwin is launched by pmcd(1) and should never be executed directly. The Install and Remove scripts notify pmcd(1) when the agent is installed or removed.

FILES

$PCP_PMDAS_DIR/darwin/help
    default help text file for the darwin metrics

$PCP_PMDAS_DIR/darwin/Install
    installation script for the darwin PMDA

$PCP_PMDAS_DIR/darwin/Remove
    undo installation script for the darwin PMDA

$PCP_LOG_DIR/pmcd/darwin.log
    default log file for error and diagnostic messages from the darwin PMDA

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).

SEE ALSO
PCPIntro(1), pmcd(1), pminfo(1) and sysctl(8).