| Compute (VM) | EC2 | Compute Engine | Per-second billing, live migration, and sustained-use discounts are automatic on GCP; instance families and networking differ. |
| Functions | Lambda | Cloud Run functions | Cloud Run functions run containers under the hood; Cloud Run blurs the FaaS/container line. Concurrency > 1 per instance is native on Cloud Run. |
| Serverless containers | ECS Fargate / App Runner | Cloud Run | Cloud Run offers request-based billing with scale-to-zero and per-instance concurrency; no task definitions or cluster concepts. |
| Kubernetes | EKS | GKE | GKE Autopilot removes node management entirely; GKE pioneered many upstream features. Control-plane pricing and node ops differ. |
| Object storage | S3 | Cloud Storage | Single global API with regional/dual/multi-region locations; strong consistency. Storage classes and retrieval semantics differ from S3 tiers. |
| Relational DB | RDS | Cloud SQL | Cloud SQL Auth Proxy / connectors and IAM DB auth differ from RDS security-group model. |
| Distributed Postgres | Aurora PostgreSQL | AlloyDB | AlloyDB adds a columnar engine and AlloyDB AI (vectors) with full Postgres compatibility; architecture and pricing differ from Aurora. |
| Document/NoSQL | DynamoDB | Firestore | Firestore is document-model with real-time listeners and offline SDKs; querying/indexing model differs sharply from DynamoDB's key-based design. |
| Wide-column | DynamoDB (large scale) | Bigtable | Bigtable is a wide-column store for high-throughput/time-series; no secondary indexes, row-key design is everything. |
| Cache | ElastiCache | Memorystore | Managed Redis/Memcached; HA, failover, and networking (private IP) models differ. |
| Queue | SQS | Cloud Tasks | Cloud Tasks targets HTTP endpoints with per-task scheduling & rate limits; it's not a pull queue like SQS. |
| Pub/Sub messaging | SNS + SQS | Pub/Sub | One service does fan-out + durable delivery, push & pull, ordering, and dead-letter — different from SNS+SQS composition. |
| Event bus | EventBridge | Eventarc | Eventarc uses CloudEvents and routes to Cloud Run/Workflows; audit-log-based event sources differ from EventBridge rules. |
| Orchestration | Step Functions | Workflows | Workflows uses a YAML/JSON DSL with connectors; pricing is per-step. Composer (Airflow) covers data-pipeline orchestration. |
| Observability | CloudWatch / X-Ray | Cloud Operations (Logging/Monitoring/Trace) | Integrated suite with Managed Service for Prometheus; log-based metrics and trace correlation differ. |
| Identity | IAM roles | IAM + service accounts | GCP separates identities (service accounts) from roles; Workload Identity Federation replaces long-lived keys for external workloads. |
| GenAI platform | Bedrock | Vertex AI | Vertex AI unifies managed models (Gemini), embeddings, vector search, tuning, and eval; SDK, grounding, and safety controls differ. |
| Vector search | OpenSearch vector | Vertex AI Vector Search | Purpose-built ANN service; AlloyDB AI/pgvector is the SQL alternative. Indexing, filtering, and pricing differ from OpenSearch. |
| IaC | AWS CDK / CloudFormation | Terraform (Google provider) | Terraform is the de-facto standard on GCP; Infrastructure Manager runs it managed. Config Connector manages resources via Kubernetes. |