There is no additional charge for Amazon ECS. You pay for AWS resources (e.g., Amazon EC2 instances or Amazon EBS volumes) you create to store and run your application. You only pay for what you use, as you use it; there are no minimum fees and no upfront commitments.
Amazon Elastic Container Service (Amazon ECS) is well suited where you need the ease of managing the clusters by letting AWS do the stuff for you. Obviously, whenever you want to run the docker based workloads, it is always better to go for either AWS ECS or AWS EKS. If you are interested in staying at AWS only and don't want to be cloud-agnostic, then go for AWS ECS instead of AWS EKS. AWS ECS is cheaper than AWS EKS and also more managed by AWS and better integrated with other AWS services. If you want to run those workloads as serverless, then AWS ECS Fargate is the best option to go with. If you already have a Kubernetes based setup that you want to migrate to AWS, then go for AWS EKS instead of AWS ECS.
There's really no reason to ever use Mesos. We switched over to Kubernetes and it's been a breath of fresh air - better CD support, easy CLI for browsing logs, no mysterious dangling redeploys. If you're looking for a tool to manage a fleet of Docker containers on VMs, Kubernetes beats Mesos by a wide margin.
One of the biggest advantages is the flexibility to change underlying EC2 instances. As the traffic or demand increases, we can easily change EC2 instances without any issues.
Amazon ECS APIs are extremely robust and one can start and stop containers by firing one post request only. So, it is not mandatory to keep the demo solutions up for every time. Just at the time of demo fire the command - make the container up and running - do the demo - down the container with API. A simple portal can control every container which helps non-technical (sales, marketing) to do the demo without keeping the solutions up for the entire time frame.
Mesos may have many frameworks. If you have Mesos installed on your servers, you may use it for many kinds of tasks. Today we're running only web applications but the idea is to install a different framework for big data soon.
Unreliable deployments that would fail for no good reason. Sometimes our Docker container would be "restarting" forever because Mesos thought it didn't have enough resources to start the container.
Impossibly slow UI. Built in React under the hood with a lot of bloatware backed in, so loading the Mesos UI on a slow internet connection was painful.
No real logging solution - it would stream "console.log()" output to the UI, but searching for logs wasn't really possible without downloading a huge file.
No built-in support for redeploying containers from a CI. We had to create a service whose whole job was to expose an HTTP endpoint that restarted a container, and then made Circle CI ping the endpoint whenever we wanted to redeploy.
Support is relatively good, although the documentation sometimes is lacking, as well as outdated in our experience, especially when we initiated the process of using this service. But once we found how to assemble things, we haven't really required support from anyone at AWS, the service works without problems so we haven't had the need to contact support, which speaks well of how ECS is built.
EKS is a Kubernetes technology and you need to learn Kubernetes and build a cluster before using it. So there's a learning curve here. ECS was easier to implement and simpler to have in our use case. It takes less time to run a workload and make it available.
Kubernetes is really great and their community is growing really fast (Google influence). We evaluated it in the beginning and it would fit for our web applications workload. We decided to proceed with Mesos because it has more potential. You may use a different framework for different kinds of tasks on Mesos. There is a Kubernetes framework for Mesos, by the way.
The autoscaling kept the performance of the services great.
We saved money by running the workloads on AWS ECS in Fargate mode by having different settings for different services to save on the hardware configuration side as well as having scheduled tasks.
