Description

This module automatically vertically scales AWS Fargate tasks when they run out memory due to an OOM Exception. It uses two Lambda functions to monitor for RunTask commands and for ECS stopped tasks. When it encounteres an OOM error it will restart the tasks automatically with double the memory.

Your tasks have to be idempotent for this to work!

For more debugging steps check out the elasticscale blog.

About ElasticScale

ElasticScale is a Solutions Architecture as a Service focusing on start-ups and scale-ups. For a fixed monthly subscription fee, we handle all your AWS workloads. Some services include:

• Migrating existing workloads to AWS
• Implementing the Zero Trust security model
• Integrating DevOps principles within your organization
• Moving to infrastructure automation (Terraform)
• Complying with ISO27001 regulations within AWS

You can pause the subscription at any time and have direct access to certified AWS professionals.

Check out our website for more information.

Requirements

Name	Version
aws	5.6.2

Providers

Name	Version
archive	2.4.0
aws	5.6.2
random	3.5.1

Modules

Name	Source	Version
dynamodb_tasks	terraform-aws-modules/dynamodb-table/aws	n/a
s3_bucket	cloudposse/cloudtrail-s3-bucket/aws	0.26.2

Resources

Name	Type
aws_cloudtrail.cf_task_trail	resource
aws_cloudwatch_event_rule.ct_event_rule	resource
aws_cloudwatch_event_rule.ecs_event_rule	resource
aws_cloudwatch_event_target.ct_event_target	resource
aws_cloudwatch_event_target.ecs_event_target	resource
aws_iam_role.lambda_ct	resource
aws_iam_role.lambda_ecs	resource
aws_lambda_function.lambda_ct	resource
aws_lambda_function.lambda_ecs	resource
aws_lambda_permission.lambda_ct_resource_policy	resource
aws_lambda_permission.lambda_ecs_resource_policy	resource
random_string.random	resource
archive_file.lambda_ct	data source
archive_file.lambda_ecs	data source
aws_iam_policy_document.lambda_ct	data source
aws_iam_policy_document.lambda_ecs	data source

Inputs

Name	Description	Type	Default	Required
iam_pass_roles	The possible IAM roles for your task definitions, this is used in the IAM policy to allow the lambda to pass the role, using [*] is a bad practice here	list(string)	n/a	yes
max_memory	The maximum amount of memory to allow a task to use in MB	number	122880	no
prefix	Value to prefix all resources with (lowercase)	string	"fargatevertiscale"	no
region	AWS region to deploy to	string	n/a	yes
setup_cloud_trail	Setup CloudTrail to capture ECS events, if you already have a trail setup to an S3 bucket you can set this to false. Without CloudTrail the module will not work	bool	true	no
tag_name	The tag name attached to RunTask command that triggers this module to run	string	"fargatevertiscale"	no
task_expires	Purge tasks from DynamoDB after this many seconds (default 7 days)	number	604800	no

Outputs

No outputs.