loom-grafana

# Grafana and the LGTM Stack Visualization, dashboards, alerting, and exploration. Scope: dashboards/panels, LogQL, TraceQL, data sources, templating, Grafana alerting. **PromQL query semantics → loom-prometheus.** ## Overview | Component | Role | Query lang | | --------- | ---- | ---------- | | **L**oki | Log aggregation; indexes labels only, not content | LogQL | | **G**rafana | Visualization, dashboards, unified alerting, Explore | — | | **T**empo | Distributed tracing; columnar Parquet, OTel-native | TraceQL | | **M**imir | Long-term, multi-tenant Prometheus storage (`remote_write`) | PromQL | Collector: **Grafana Alloy** (OTel Collector distribution). Grafana Agent is EOL (2025-11-01) — migrate. ## Dashboard Design **Hierarchy:** Overview → Service → Component → Deep Dive. **Signals:** RED (Rate/Errors/Duration) for services, USE (Utilization/Saturation/Errors) for resources. Variable-driven, 24-column grid, `< 15` panels/dashboard. ### Panel types | Panel | Best for | | ----- | -------- | | Time Series | trends: rates, latency, resource usage (default; replaces removed Graph) | | Stat | single current value / sparkline | | Gauge / Bar Gauge | progress toward a limit / Top-N comparison | | Table | structured rows: service lists, error details | | Heatmap | distribution over time (latency buckets); renders native histograms | | Pie | proportions (use sparingly) | | Logs / Traces | Loki streams / Tempo trace view | ### Panel config - **Titles** include the unit +...