Alert thresholds depend on the nature of your applications. Some queries may have arbitrary tolerance thresholds. Building an efficient monitoring platform takes time. 😉
1 Prometheus alerting rule for PHP-FPM. Exported via bakins/php-fpm-exporter. These rules cover critical and warning conditions — copy and paste the YAML into your Prometheus configuration.
groups:
- name: BakinsFpmExporter
rules:
- alert: PHP-FPMMax-childrenReached
expr: sum(increase(phpfpm_max_children_reached_total[5m])) by (instance) > 3
for: 0m
labels:
severity: warning
annotations:
summary: PHP-FPM max-children reached (instance {{ $labels.instance }})
description: "PHP-FPM reached max children on {{ $labels.instance }} ({{ $value }} times in the last 5m)\n VALUE = {{ $value }}\n LABELS = {{ $labels }}" wget https://raw.githubusercontent.com/samber/awesome-prometheus-alerts/refs/heads/master/dist/rules/php-fpm/bakins-fpm-exporter.yml
PHP-FPM reached max children on {{ $labels.instance }} ({{ $value }} times in the last 5m)
- alert: PHP-FPMMax-childrenReached
expr: sum(increase(phpfpm_max_children_reached_total[5m])) by (instance) > 3
for: 0m
labels:
severity: warning
annotations:
summary: PHP-FPM max-children reached (instance {{ $labels.instance }})
description: "PHP-FPM reached max children on {{ $labels.instance }} ({{ $value }} times in the last 5m)\n VALUE = {{ $value }}\n LABELS = {{ $labels }}"