Cloud Run

Serverless containers

Cloud Run runs any container that listens on the port given in the PORT environment variable. You deploy an image (or source code, which Cloud Build turns into an image) and Google manages servers, TLS, scaling and load balancing. Services handle HTTP or gRPC requests; jobs run containers to completion for batch work. Each instance handles many requests at once, set by concurrency (default 80, up to 1000), and the number of instances scales with traffic, down to zero when idle unless you set minimum instances to avoid cold starts. Every deploy creates an immutable revision, and you can split traffic between revisions for canary releases. Access can be public, or restricted so callers need the Cloud Run Invoker role. Containers should be stateless: anything written to the local filesystem lives in memory and disappears with the instance.

Deploy from source, then a canary

--no-traffic deploys a revision without sending users to it.

gcloud run deploy orders-api --source . --region=asia-south1 \
  --service-account=orders-api@shop-dev-123456.iam.gserviceaccount.com \
  --min-instances=1 --max-instances=20 --concurrency=80 --no-allow-unauthenticated

# next release: deploy with a tag, test, then shift 10% of traffic
gcloud run deploy orders-api --source . --region=asia-south1 --no-traffic --tag=canary
gcloud run services update-traffic orders-api --region=asia-south1 --to-tags=canary=10

# a batch job
gcloud run jobs deploy nightly-report --image=asia-south1-docker.pkg.dev/shop-dev-123456/apps/report:1.0
gcloud run jobs execute nightly-report

Shared autos at a station

Each Cloud Run instance is an auto that takes several passengers (concurrency). When the train arrives more autos appear; at 2 a.m. none wait around unless you pay one driver to stay (minimum instances).

त्वरित जाँच: A Cloud Run service has noticeable cold starts after quiet periods. What is the simplest fix?

• Lower concurrency to 1
• Switch to a zonal disk
• Make the service public
• Set minimum instances to 1 or more