drenv metrics

The drenv stress-test report command automatically collects system metrics from Netdata if it is running. This is important to correlate test failures to system load.

Installing Netdata

macOS:

brew install netdata

Linux:

curl --fail --silent --show-error --location --output /tmp/netdata-kickstart.sh \
    https://get.netdata.cloud/kickstart.sh
bash /tmp/netdata-kickstart.sh --no-updates --stable-channel

Configuring netdata

For stress testing, configure Netdata to use minimal resources and store data on disk (persists across restarts, uses less memory).

Edit /opt/homebrew/etc/netdata/netdata.conf (macOS) or /etc/netdata/netdata.conf (Linux):

[cloud]
enable = no

[global]
update every = 15
memory mode = dbengine

[db]
mode = dbengine
dbengine multihost disk space MB = 1024

This configuration:

Collects metrics every 15 seconds (good balance of detail vs overhead)
Stores data on disk (up to 1 GB, keeps weeks of history)
Uses minimal memory (~64 MB for cache)
Safe to leave running permanently

Start netdata service

Start Netdata before running a stress test:

macOS:

brew services start netdata

Linux:

sudo systemctl start netdata

Verify Netdata is running by opening http://localhost:19999 in a browser.

Stop netdata service

Stop Netdata after collecting metrics:

macOS:

brew services stop netdata

Linux:

sudo systemctl stop netdata

Remote access (Linux)

By default Netdata listens on localhost only. To access it from another machine, configure it to listen on all interfaces.

Edit /etc/netdata/netdata.conf:

[web]
bind to = 0.0.0.0

Restart Netdata and open the firewall port:

sudo systemctl restart netdata
sudo firewall-cmd --zone=public --add-port=19999/tcp --permanent
sudo firewall-cmd --reload

Then access Netdata at http://<host>:19999.