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adamgordonbell · 3 years ago
Author here. I didn't expect this to show up here. I found containers on lambda to work really well. I can easily test them locally and they scale to zero when I'm not using them in AWS. So it's perfect for things that are idle a lot.

I have a follow up coming where I use go in a container, and the request speed got a lot better.

The service in this article is my html to text convert, so having a container where I could install OS-dependencies was crucial to getting this working. It's covered here and here:

https://news.ycombinator.com/item?id=30829568

https://earthly-tools.com/text-mode

squeaky-clean · 3 years ago
> I have a follow up coming where I use go in a container, and the request speed got a lot better.

My team transitioned a lightweight python based lambda from zip to container based and we also saw a small (but definitely real) speedup in request time. I'm not the one who did the benchmarking, but iirc it was about 10ms faster. From ~50ms to ~40ms or so.

edit: originally phrased it backwards to seem like container method was slower.

soren1 · 3 years ago
My experience has been the opposite, with simple python docker containers showing noticeably slower cold starts than python zips. I've also found the size of the zip package matters (smaller is faster). However things change over time, maybe there have been recent improvements?

Specifically regarding cold starts of lambda instances, I recall this excellent article from Jan 2021 which measures cold start latencies for a variety of AWS lambda runtimes:

https://mikhail.io/serverless/coldstarts/aws/languages/

I would love to see a 2022 update.

jaimehrubiks · 3 years ago
Are you saying latency is lower on container than plain python?

I recently made a project for the company and didn't even consider containers (which I love btw) because I though I could save some ms without container.

Do you know if lambda containers performance is also good in nodejs? I need to have python and nodejs lambdas.

Deleted Comment

excuses_ · 3 years ago
I had much better experience with GCP Cloud Run. Prepare a OCI/Docker image, type `gcloud run` with a few flags and you’re done. In 2021 they added a bunch of features which in my opinion make Cloud Run one of the most trivial ways of deploying containers indented for production usage.
nogbit · 3 years ago
Simply the best cloud service from any of the three big CSP’s bar none. The day AWS supports this more out of the box on Lambda (no, I will not use your required base image or signatures) will be the day containers and serverless become one (like it is already on GCP).
chrisweekly · 3 years ago
Fly.io isn't one of the "three big CSP's" but they are awesome.
holografix · 3 years ago
Prepare image…? Just let buildpacks sort it out and forget the Dockerfile ever existed.
gadflyinyoureye · 3 years ago
We're trying this out at a large insurance company. Historically actuarial teams created excel workbooks, r code, and python. Then those models were given to development teams to implement in a different language. As one might guess there were loads of bugs and the process was slow. Now we're going to deploy an R lambda that owned by DevOps which integrates all the I/O into dataframes. The lambda calls a calculation in R that takes those dataframes and returns a dataframe answer. If all goes well (prototype works fine), we saved probably 500k and 6 months.
carfacts · 3 years ago
You’ll have to deal with lambda cold starts if you want it to be performant:

> When the Lambda service receives a request to run a function via the Lambda API, the service first prepares an execution environment. During this step, the service downloads the code for the function, which is stored in an internal Amazon S3 bucket (or in Amazon Elastic Container Registry if the function uses container packaging). It then creates an environment with the memory, runtime, and configuration specified. Once complete, Lambda runs any initialization code outside of the event handler before finally running the handler code.

https://aws.amazon.com/blogs/compute/operating-lambda-perfor...

mjb · 3 years ago
It's not entirely accurate that Lambda pulls container images from ECR at start-up time. Here's me talking about what happens behind the scenes (which, in the real world, often makes things orders of magnitude faster than a full container pull): https://www.youtube.com/watch?v=A-7j0QlGwFk

But your broader point is correct. Cold starts are a challenge, but they're one that the team is constantly working on and improving. You can also help reduce cold-start time by picking languages without heavy VMs (Go, Rust, etc), but reducing work done in 'static' code, and by minimizing the size of your container image. All those things will get less important over time, but they all can have a huge impact on cold-starts now.

Another option is Lambda Provisioned concurrency, which allows you to pay a small amount to control how many sandboxes Lambda keeps warm on your behalf: https://docs.aws.amazon.com/lambda/latest/dg/provisioned-con...

afandian · 3 years ago
Pardon the ignorance, but is the state of lambda containers considered to be single-threaded? Or can they serve requests in parallel?

If I had a Spring Java (well, Kotlin) app that processes stuff off SQS (large startup time but potentially very high parallelism), would you recommend running ECS containers and scale them up based on SQS back-pressure? Or would you package them up as Lambdas with provisioned capacity? Throughput will be fairly consistent (never zero) and occasionally bursty.

daenz · 3 years ago
I'm not an expert in this area, but have you all considered using CRIU[0] (checkpoint restore in userspace) for container-based Lambdas to allow users to snapshot their containers after most of the a language's VM (like Python) has performed its startup? Do you think this would reduce startup times?

0. https://criu.org/Docker

daenz · 3 years ago
They have a feature called "provisioned concurrency" where basically one "instance" of your lambda (or however many you want to configure) stays running warm, so that it can handle requests quickly.

I know it defeats the conceptual purpose of serverless, but it's a nice workaround while cloud platforms work on mitigating the cold start problem.

andrew_ · 3 years ago
That'll also cost you $$$$ and takes any provisioned lambda out of the free tier. Also note that only your specified number of instances will stay warm, meaning if your lambda needs to scale up, you risk slow cold starts on additional instances outside of the number you provisioned. You could specify the number of reserved concurrent images (limiting the number that run) but that also costs money and will eat int your quota.

Using containers for lambda is generally a bad idea for anything TypeScript/JavaScript that handles a realtime request - you just can't beat the speed of a single JavaScript file (compiled, in the case of TS). AWS CDK now ships with the NodeJSFunction as well, which makes generating those a breeze with ESBuild.

onphonenow · 3 years ago
I've had some pretty good luck sliming things down as well. That's a win win usually for even non-lambda cases (trying things like docker-slim / switching stuff to go that needs a quick response).

That said, the $2-5/month is fine as well for some cases.

catlifeonmars · 3 years ago
It’s nice to have that dial. Running lambda with provisioned concurrency is still a very managed experience: much different than running a container cluster.
sam0x17 · 3 years ago
If cold starts are at all an issue for whatever use-case, you can just do a warming job like we do (in our case it's built into Ruby on Jets). We find invoking every 30 seconds is enough to never have a cold start. It's still quite cheap as well. The lambda portion of our bill (with tons of platform usage) is still incredibly low / low double digits.

Just doing a warming job with no other usage falls well within free tier usage, I can confirm.

booi · 3 years ago
This is definitely an issue especially with infrequently accessed functions but I've seen cold start issues regardless. I assume some scaling events will cause cold starts (measured in seconds).

There's a good argument to go with packaged code instead of containers if you can manage the development complication and versioning (cold starts measured in milliseconds).

cebert · 3 years ago
My team owns a Node 14 JS lambda application that is completely serverless. We’re focused on keeping our lambdas small with single responsibilities and leverage lambda layers for anything common across multiple lambdas. Cold starts are a concern, but is very negligible (< 100ms tops) and unnoticed by our client apps. We host all of our static web and JS assets via Cloud Front so they load quickly. If a user happened to visit our site when a lambda incurred a cold start, it’s not perceptible. We were much more worried initially about cold starts than it turned out we needed to be. Keeping lambdas small, picking a good language for the job, and leveraging lambda layers help minimize this a lot.
fswd · 3 years ago
Lambda is Greek for CGI script.
mjb · 3 years ago
In a way, sure.

But Lambda also does things that CGI didn't do: dynamic auto-scaling, integration with queues and streams for async processing, strong security isolation with fine-grained authorization, host failure detection and recovery, datacenter failure resilience, and many other things. The interface being familiar and relatively analogous to existing things is intentional. The point is to be different where being different helps, and familiar where being different doesn't help.

tedunangst · 3 years ago
You get like 90% of that dropping your CGI directory on NFS shared among multiple hosts. AWS offers a full featured host environment, so you don't have to build that part, but the part you write is quite similar.
throwaway2016a · 3 years ago
As someone who has been around long enough to actually remember setting up /cgi-bin/... there is a lot more to lambdas.

They are scalable (including, importantly, down to zero!), have their own dedicated resources for each process, and are pretty efficient at being put to sleep and woken up. Plus the code is immutable by default and you get a lot out of the box like logging and setting limits.

I wouldn't start a new project with CGI at all right now but I use Lambda constantly.

recuter · 3 years ago
In addition to what the other replies said I'd like to offer the following observation:

Lambda is the control plane running inside an "AWS OS" context, that means it has access to internal apis with scoped permissions. Most commonly people discuss user facing lambdas on the edge, however you are not obligated to expose it to the world.

If you do choose to go the cloud route understand that your account activities generate quite a lot of data. Simplest example would be custom CloudWatch events generated from say autoscaling groups i.e. "Server 23 has ram usage above some moving average threshold" => kick off lambda => custom logic (send email/slack, reboot server, spin up more instances, whatever).

People who like middle brow dismissals would say "what does it matter where the script runs, it could just as easily be running on the instance itself" - to them I say, pain is the best teacher. :)

quaffapint · 3 years ago
We are using a container hosting .net6 with our lambda. We use it where I think lambdas really work well, that is to process queue items off of SQS. It works well with the dead-letter queue as well. We dont notice any performance issues, but this is just a processor, so we don't need to worry about real-time responses either.
cebert · 3 years ago
What was the thought behind processing SQS messages with a dotnet 6 containized lambda instead of a Node or Python lambda?
jugg1es · 3 years ago
Have you used .NET recently? This is sort of a weird question. Not everyone uses node or python.
victor106 · 3 years ago
I found using AWS Copilot to deploy to AWS Fargate easy to deploy, maintain and scale.
nogbit · 3 years ago
Until it it fails, and the backing CF errors and won’t resolve itself for over 24rs. Bit twice, never again with Copilot. Good idea they had, just shaky foundation.
logic_beats_pro · 3 years ago
CF = Cloud Formation?
vorpalhex · 3 years ago
I went down the rabbithole of wanting to build my own lightweight Lambda, only to wonder if Lambda is just distributed CGI by another name.
dsanchez97 · 3 years ago
I think CGI is a good high level way of think about AWS Lambda and other Serverless compute platforms. I think the key innovations are the integrations with cloud services, and the scaling/economic model. Videos like the one linked below really demonstrate the level of optimizations implemented to make this work on the "cloud" scale. I think Serverless Compute platforms are going to become a really meaningful part of the software development ecosystem.

[1] https://www.youtube.com/watch?v=A-7j0QlGwFk&ab_channel=Insid...

tyingq · 3 years ago
Feels pretty similar to any typical fastcgi implementation with pools, scaling up/down, separate spaces for initialization code and per-request code, etc.
zevv · 3 years ago
And, was it?