| Feature/Aspect | GreptimeDB | Grafana Loki |
|---|---|---|
| Data Model | Unified Observability Database | Log Aggregation System |
| Multi-model | Metrics, Logs & Traces in one database | Logs only (requires separate systems for metrics/traces) |
| Indexing Strategy | Full-text indexing, inverted index, vector search | Label-based indexing only (no full-text indexing) |
| Ingestion Protocols | SQL gRPC InfluxDB Line Protocol Prometheus Remote Storage OpenTelemetry Loki Push API Elasticsearch Bulk API HTTP API | HTTP Push API Promtail Fluent Bit Vector LogQL |
| Query Languages | SQL & PromQL (dual interface) | LogQL |
| Log Processing | Built-in Pipeline engine for log transformation and parsing | Basic parsing with structured metadata |
| Storage Format | Apache Parquet (columnar) | Custom chunks (compressed logs) |
| Storage Architecture | Compute-storage separation with object storage (S3, etc.) | Distributed with object storage backends |
| Query Performance | Sub-second response with full-text search and vector search | Fast label-based queries, slower text searches |
| Deployment Options | Single node, cluster, cloud-native, edge deployment | Simple scalable mode, microservices mode |
| Use Cases | Unified observability, real-time analytics, IoT monitoring, log analysis | Log aggregation, troubleshooting, audit trails |
| Integration | Native SQL/PromQL support, OpenTelemetry, multi-protocol | Deep Grafana integration, Prometheus-like experience |
| License | Apache 2.0 | Apache 2.0 |
| Multi-tenancy | Built-in multi-tenancy with isolation | Native multi-tenant architecture |
| Written Language | Rust | Go |
| Operational Complexity | Single system for all observability data | Requires additional systems for complete observability stack |