ECS Scaling at 20% CPU usage.

[connoromalleyatwork]

What does this change?

Adds target scaling to ECS for tag page rendering in both CODE and PROD.

Target scaling was added to the cdk in GuLoadBalancedAppExperimental in pr ECS CPU Target Scaling - #2962

[github-actions]

🚀 Image pushed to AWS ECR

Image digest: sha256:32c4d87d751a767c56cc9d7fe6dfb7843df38dee560fa70300842e6eb258273e

🐛 Run the image locally

The following can be used to run the image locally:

# Refer to image using the immutable digest. Find alternatives below.
IMAGE_IDENTIFIER="@sha256:32c4d87d751a767c56cc9d7fe6dfb7843df38dee560fa70300842e6eb258273e"

# Refer to image using branch tag
# IMAGE_IDENTIFIER=":branch-dcr-1percent"

# Refer to image using build tag
# IMAGE_IDENTIFIER=":build-31167"

# Set environment variables for the AWS CLI
AWS_PROFILE="<A_PROFILE_FROM_JANUS>"
AWS_DEFAULT_REGION="eu-west-1"

IMAGE_ACCOUNT_ID=$(aws ssm get-parameter --name /organisation/accounts/artifacts --query "Parameter.Value" --output text)
REGISTRY="${IMAGE_ACCOUNT_ID}.dkr.ecr.${AWS_DEFAULT_REGION}.amazonaws.com"
IMAGE="${REGISTRY}/guardian/dotcom-rendering${IMAGE_IDENTIFIER}"

# Login to AWS ECR https://docs.aws.amazon.com/AmazonECR/latest/userguide/registry_auth.html
aws ecr get-login-password | docker login --username AWS --password-stdin $REGISTRY

# Pull the image
docker pull $IMAGE

# Run the image. You'll likely need to set additional flags. See https://docs.docker.com/reference/cli/docker/container/run.
docker run $IMAGE

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From guardian/actions-publish-image.

[github-actions]

Deploy build 31167 of dotcom:rendering-all to CODE

All deployment options

• Deploy build 31167 of dotcom:rendering-all to CODE
• Deploy parts of build 31167 to CODE by previewing it first
• What's on CODE right now?

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From guardian/actions-riff-raff.

[github-actions]

Deploy build 3165 of dotcom:ab-testing to CODE

All deployment options

• Deploy build 3165 of dotcom:ab-testing to CODE
• Deploy parts of build 3165 to CODE by previewing it first
• What's on CODE right now?

---

From guardian/actions-riff-raff.

[akash1810]

IIUC we don't currently scale EC2 CODE - do we need to scale ECS CODE? Not a blocking comment, as we can update in a later PR.

[connoromalleyatwork]

The default is Duration.seconds(300), which I actually think I like more as it gives more time to prevent fluctuations in capacity.

We had the 60 seconds before this change when doing our load testing, however I think that may have been to speed up scaling events to reduce wait time to watch them happen. Not for any meaningful reason.

[connoromalleyatwork]

@akash1810 and I discussed this and we are going to stick with 60 seconds for each cooldown for now. We can tune this more later!

60 seconds seams reasonable for now, and it is hard to know how this will impact scaling and the services ability to maintain its SLI under increasing load without watching it in production. We did a load test in code and it coped fine, so we have no reason to believe 60 seconds is a bad choice.

[gu-prout]

Seen on PROD (merged by @connoromalleyatwork 9 minutes and 4 seconds ago) Please check your changes!