brandon/oam
1
0
Fork 0
mirror of https://gitea.com/mcereda/oam.git synced 2026-02-08 21:34:25 +00:00
Code Issues Packages Projects Releases Wiki Activity

chore(aws/ecs): improve section about capacity providers

Browse Source
This commit is contained in:
Michele Cereda
2026-01-14 13:19:07 +01:00
parent afda865ecc
commit cba9d9193e
1 changed files with 50 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files

74
knowledge base/cloud computing/aws/ecs.md
View File

@@ -397,14 +397,48 @@ Clusters can contain a mix of tasks that are hosted on Fargate, Amazon EC2 insta
Tasks can run on Fargate or EC2 infrastructure, as defined by their [launch type] or a capacity provider strategy.<br/>
Capacity providers offer enhanced flexibility and advanced features for capacity management compared to launch types.
Each cluster can have one or more _capacity providers_, and an optional _capacity provider strategy_.
Each cluster can have one or more _capacity providers_, and one optional
[_capacity provider strategy_][capacity provider strategies].
To run tasks on Fargate, one only needs to associate one or more of the pre-defined Fargate-specific capacity providers
(`FARGATE`, `FARGATE_SPOT`) with the cluster.<br/>
Leveraging the Fargate providers lifts the need to create or manage that cluster's capacity.
> [!warning]
> One **cannot** update a service that is using only an Auto Scaling Group capacity provider to use a Fargate-specific
> one, and vice versa.
Clusters _can_ contain a mix of Fargate and Auto Scaling group capacity providers.
<details style='padding: 0 0 1rem 1rem'>
```json
{
"clusterName": "some-cluster",
"capacityProviders": [
"FARGATE",
"FARGATE_SPOT",
"some-custom-ec2-capacity-provider"
]
}
```
### Capacity provider strategies
Capacity provider strategies determine how tasks are spread across a cluster's capacity providers.<br/>
Cluster that do **not** have a default capacity provider strategy will spread tasks **wherever** they find enough
capacity.<br/>
One can assign a **default** capacity provider strategy to a cluster.
Capacity provider strategies determine how tasks are spread across a cluster's capacity providers.
One must associate at least one capacity provider with a cluster **before** specifying a capacity provider strategy
for it.<br/>
Strategies allow to specify a maximum of 20 capacity providers.
> [!warning]
> Even if clusters _can_ contain a mix of Fargate and Auto Scaling group capacity providers, capacity provider
> strategies can currently only contain **either** Fargate **or** Auto Scaling group capacity providers, but
> **not both**.
One can assign a **default** capacity provider strategy to a cluster.<br/>
Clusters that do **not** have a default capacity provider strategy will spread their tasks onto **whatever** configured
provider will have enough capacity at the moment of deployment.
<details style='padding: 0 0 1rem 1rem'>
@@ -434,9 +468,10 @@ When running a standalone task or creating a service, one _can_ specify a capaci
cluster's default one.
> [!important]
> The default capacity provider strategy **only** applies when one specifies **neither** a launch type **nor** a
> capacity provider strategy for a task or service.<br/>
> Should **any** of these parameters be provided, the cluster's default strategy will be **ignored**.
> The cluster's default capacity provider strategy **only** applies when a task or service specifies **neither** a
> launch type **nor** its own capacity provider strategy.<br/>
> Should a task or service be configured with **either** of these parameters, it will **ignore** the cluster's
> default strategy.
<details style='padding: 0 0 1rem 1rem'>
<summary>Override the cluster's default strategy</summary>
@@ -465,26 +500,15 @@ cluster's default one.
</details>
One must associate a capacity provider with a cluster **before** associating it with a capacity provider strategy.<br/>
Strategies allow to specify a maximum of 20 capacity providers.
Strategies' weight value defaults to `1` when creating it from the Console, and to `0` if using the API or CLI.
To run tasks on Fargate, one only needs to associate one or more of the pre-defined Fargate-specific capacity providers
with the cluster.<br/>
Leveraging the Fargate providers lifts the need to create or manage that cluster's capacity.
Clusters _can_ contain a mix of Fargate and Auto Scaling group capacity providers. However, a capacity provider strategy
can only contain either Fargate or Auto Scaling group capacity providers, but **not both**.
One **cannot** update a service that is using an Auto Scaling Group capacity provider to use a Fargate one, and
vice versa.
A strategy's capacity provider can have a defined `base` value. This determines how many **guaranteed** tasks that
provider will be given **as minimum** when enough replicas are requested.<br/>
Setting the `base` value higher than the service or standalone task's `desiredCount` only results in `desiredCount`
tasks being placed on that provider. If no `base` value is specified for a provider, it defaults to `0`.<br/>
When multiple capacity providers are specified within a strategy, only **one** of them can have a defined `base` value.
tasks being placed on that provider. If no `base` value is specified for a provider, it defaults to `0`.
> [!warning]
> Only **one** capacity provider can have a `base` value other than `0` in a strategy.
The `weight` value determines **the relative ratio** of tasks to execute over the long run.<br/>
This value is taken into account **only after the `base` values are satisfied**.<br/>
@@ -561,7 +585,7 @@ Provider 3 is `some-custom-ec2-capacity-provider`, with a weight of `0` and base
```
`some-custom-ec2-capacity-provider` will run tasks just for being the provider with the `base` value defined.<br/>
Aside assigning it the 2 base tasks as per configuration, the scheduler will just ignore
After assigning it the 2 base tasks as per configuration, the scheduler will just ignore
`some-custom-ec2-capacity-provider` due to its weight being `0`.
Sum of the remaining weights: `1 + 19 = 20`.<br/>
@@ -1855,6 +1879,7 @@ Specify a supported value for the task CPU and memory in your task definition.
- [The Ultimate Beginner's Guide to AWS ECS]
- [Amazon Amazon ECS launch types and capacity providers]
- [Effectively Using Spot Instances in AWS ECS for Production Workloads]
- [Avoiding Common Pitfalls with ECS Capacity Providers and Auto Scaling]
<!--
Reference
@@ -1935,6 +1960,7 @@ Specify a supported value for the task CPU and memory in your task definition.
[308 Permanent Redirect]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Status/308
[a step-by-step guide to enabling amazon ecs exec]: https://medium.com/@mariotolic/a-step-by-step-guide-to-enabling-amazon-ecs-exec-a88b05858709
[attach ebs volume to aws ecs fargate]: https://medium.com/@shujaatsscripts/attach-ebs-volume-to-aws-ecs-fargate-e23fea7bb1a7
[Avoiding Common Pitfalls with ECS Capacity Providers and Auto Scaling]: https://medium.com/@bounouh.fedi/avoiding-common-pitfalls-with-ecs-capacity-providers-and-auto-scaling-24899ab6fc25
[AWS Fargate Pricing Explained]: https://www.vantage.sh/blog/fargate-pricing
[aws-cloudmap-prometheus-sd]: https://github.com/awslabs/aws-cloudmap-prometheus-sd
[ECS pricing]: https://awsfundamentals.com/blog/amazon-ecs-pricing