--- title: You’re Paying for Servers You’re Not Using. AWS Lambda... description: AWS Lambda is a serverless compute service that charges only for actual execution time, eliminating idle server costs. Functions are stateless, triggered by... canonical: https://daily.dev/posts/you-re-paying-for-servers-you-re-not-using-aws-lambda-fixes-that--pbzq6ixun twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: You’re Paying for Servers You’re Not Using. AWS Lambda Fixes That. | daily.dev og:description: AWS Lambda is a serverless compute service that charges only for actual execution time, eliminating idle server costs. Functions are stateless, triggered by... og:url: https://daily.dev/posts/you-re-paying-for-servers-you-re-not-using-aws-lambda-fixes-that--pbzq6ixun og:image: https://api.daily.dev/og/posts/pBzq6IxUn.png og:image:alt: You’re Paying for Servers You’re Not Using. AWS Lambda Fixes That. og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # You’re Paying for Servers You’re Not Using. AWS Lambda Fixes That. **[Medium](https://daily.dev/sources/medium_js)** · 7 min read · 0 upvotes · 0 comments ## Summary AWS Lambda is a serverless compute service that charges only for actual execution time, eliminating idle server costs. Functions are stateless, triggered by events (S3, API Gateway, EventBridge, etc.), and scale automatically. Key tradeoffs include cold starts — especially painful for Java runtimes — which can be mitigated with Provisioned Concurrency or lighter runtimes. Pricing is per-invocation and per GB-second, with a generous permanent free tier. Lambda runs on Firecracker microVMs for fast, isolated execution. It excels at event-driven processing, unpredictable traffic, and async workloads, but containers (ECS/Fargate) are better for long-running processes or large deployment packages. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What causes cold starts in AWS Lambda and how can I reduce them? A cold start happens when AWS spins up a new execution environment from scratch after a function hasn't been invoked recently, involving downloading the code package, initializing the runtime, and running initialization code outside the handler. This takes a few hundred milliseconds to a couple seconds, hitting hardest with Java or .NET runtimes and large deployment packages. Fixes include Provisioned Concurrency, optimizing package size, or switching to lighter runtimes like Python or Node.js. _Teams tuning latency-sensitive Lambda APIs can follow ongoing serverless coverage on daily.dev._ ### How much does AWS Lambda cost compared to running an EC2 instance 24/7? Lambda charges about $0.20 per million requests plus $0.0000166667 per GB-second, so running a 128 MB function for 100ms a million times costs roughly $2.10, versus paying for an EC2 instance running continuously regardless of usage. Lambda also includes a permanent free tier of one million invocations and 400,000 GB-seconds monthly. Lambda wins for variable or unpredictable traffic; EC2 wins for constant, always-on workloads. _Engineers comparing serverless versus EC2 costs can track pricing analyses like this on daily.dev._ ### What are the deployment size and runtime limits for AWS Lambda functions? Lambda deployment packages are capped at 50 MB zipped, 250 MB unzipped, or 10 GB when using container images, and functions can run for a maximum of 15 minutes. Workloads exceeding these limits, such as a 4 GB machine learning model needing 20 minutes of inference time, should use Fargate or SageMaker instead. Lambda's execution environments run on Firecracker microVMs that boot in under 125 milliseconds. _Developers deciding between Lambda, Fargate, or SageMaker for a workload can follow these tradeoffs on daily.dev._ ## Similar posts on daily.dev - [Serverless is the ultimate place to experiment](https://daily.dev/posts/serverless-is-the-ultimate-place-to-experiment-kz51wsjw2) · Serverless · 0 upvotes · 0 comments - [Serverless Architecture: When to Use It \(and When Not To\)](https://daily.dev/posts/serverless-architecture-when-to-use-it-and-when-not-to--3trxabnfp) · Syncfusion · 0 upvotes · 0 comments - [Medium](https://daily.dev/posts/medium-zrfshok4c) · Medium · 0 upvotes · 0 comments --- Tags: [#cloud](https://daily.dev/tags/cloud), [#aws](https://daily.dev/tags/aws), [#architecture](https://daily.dev/tags/architecture), [#serverless](https://daily.dev/tags/serverless), [#aws-lambda](https://daily.dev/tags/aws-lambda) [View this post on daily.dev](https://daily.dev/posts/you-re-paying-for-servers-you-re-not-using-aws-lambda-fixes-that--pbzq6ixun) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"You’re Paying for Servers You’re Not Using. 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