lamby VS buildah

AWS Serverless Hero Ken Collins maintains a very popular Rails-Lambda package. After some discussion, he added the capability to track Proactive Initializations and came to a similar conclusion - in his case after a 3-day test using Ruby with a custom runtime, 80% of initializations were proactive:

This means the Monitoring with CloudWatch is just half the picture. But how much is your application potentially benefiting from proactive inits? Since Lamby v5.1.0, you can now find out easily using CloudWatch Metrics. To turn metrics on, enable the config like so:

After years of smashing Cloud & Rails together, I've come up with an idea. Better than an idea, a working specification! One where us Rails & Lambda enthusiasts can once again "console into" our "servers" and execute CLI tasks like migrations or interact via our beloved IRB friend, the Rails console. Today, I would like to present, the Lambda Console project. An open specification proposal for any AWS Lambda runtime to adopt.

> Does this mean you have a cron job just pinging the serverless function every 3 minutes? I'm curious how much this adds on to your costs. It means that the whole "don't pay for non-usage" thing is not quite true, but maybe it's still significantly cheaper than running an EC2 instance or whatnot. I'm curious about the cost calculation here.

Yes, specifically it kicks off a Lambda function that does a parallel GET to our website at a special endpoint that has a 100ms "wait" and basic DB call. This keeps the lambda process alive/in-memory.

To keep a function alive costs ~125ms (100ms wait + 25ms full func roundtrip). every 3 minutes. ~0.041% of 1x CPU time. Our website server costs are tiny and lower for Staging and UAT. Benefit - can scale to 1000x (AWS Limit) servers at the speed of your cold start time.

> Another thing I'm curious about, since you have a container-based deployment, did you compare with Fargate?

Yes we use Fargate for our core product which is built in Rails before containers could be deployed in Lambda. Rails works fine on Lambda[0] but the transition cost wasn't worth it for us. Fargate is great, but as you point out it is expensive if your application isn't a user heavy one like ours. To be highly available, we always have a minimum of 2 online but we're a b2b application so our night usage, 10pm-6am is zero. But I have 2 machines just sitting there. This is why i love Lambda >> Fargate.

Also, scalaing Fargate machines is slow if you get a traffic spike.

[0] https://github.com/rails-lambda/lamby

If you are curious to learn more about how Rails & Lambda work together, check out our Lamby project. The architecture of Lambda Containers works so well with Rails since our framework distills everything from HTTP, Jobs, Events, & WebSocket connections down to amazing CMD Docker contract. The architecture above at the proxy layer was easy to build and connect up to our single delegate function, Lamby.cmd. Shown below.

Today I am happy to announce that Lamby (Simple Rails & AWS Lambda Integration using Rack) now demonstrates just how easy it is to use multi-platform arm64 images on AWS Lambda. If this sounds interesting to you, jump right into our Quick Start guide and deploy a new Rails 7 on Ruby 3.2 Ubuntu image to see it for yourself.

(I have not actually used this myself). The folks over at CustomInk maintain Lamby, a project to run Rails in a quickly-bootable Lambda environment. Might be worth checking out, if you otherwise do enjoy working with Rails: https://lamby.custominktech.com

In any case you can try out https://github.com/customink/lamby which is a gem responsible to allow to run a ror app native on aws lambda.

For the task of building the graph image, my first idea was to rely on buildah. In fact, our design was already heavily relying on containers/image for all things regarding copying images from one registry to the other, or from one registry to an archive. The obvious choice was to use the same suite of modules in order to keep dependencies to a minimum.

I appreciate that podman can run daemonless, but I've gotten tired of waiting for them to implement heredoc support and have continued to use docker.

You do realize that, under the hood, buildah uses a container engine (runc by default)? See https://github.com/containers/buildah/blob/main/docs/buildah...

buildah

I found this small tutorial: https://github.com/containers/buildah/blob/main/docs/tutorials/04-include-in-your-build-tool.md and it works.

# https://github.com/containers/buildah/issues/3666 volume /var/lib/containers

Last week, Buildah version 1.29 was also released. The prune command has been added to clean intermediate images as well as the build and mount cache.  Support for the –group-add option to the from and build commands was added. One useful feature of this, it to use the –group-add keep-groups option, which allows rootless users to take advantage of their group access to file and devices mounted into the build containers. And the –cache-from and –cache-to options for the build command now allow for multiple sources. This can be used to improve the speed of builds, especially in CI/CD environments.

Unfortunately this syntax is not generally supported yet - it's only supported with the buildkit backend and only landed in the 1.3 "labs" release. It was moved to stable in early 2022 (see https://github.com/moby/buildkit/issues/2574), so that seems to be better, but I think may still require a syntax directive to enable.

Many other dockerfile build tools still don't support it, e.g. buildah (see https://github.com/containers/buildah/issues/3474)

Useful now if you have control over the environment your images are being built in, but I'm excited to the future where it's commonplace!

For more information regarding the bundled tools see: CRI tools.