To summarise:
- It's correct that you can't have provisioned concurrency for $LATEST.
- You need to publish new versions after each update.
- You can create an alias, which you need to update to refer to the newest published version each time.
- The alias can have provisioned concurrency.
- In API Gateway, you can paste the ARN of the alias in the integration target. (You may also be able to type lambda-name:alias, but I've not tried that.)
Thanks for the comments everyone. Answer from Phil Endecott on repost.aws
Amazon Web Services
docs.aws.amazon.com › aws lambda › developer guide › understanding lambda function scaling › configuring provisioned concurrency for a function
Configuring provisioned concurrency for a function - AWS Lambda
For example, to configure provisioned concurrency with the AWS Command Line Interface (CLI), use the put-provisioned-concurrency-config command. The following command allocates 100 units of provisioned concurrency for the BLUE alias of a function named my-function: aws lambda put-provisioned-concurrency-config --function-name my-function \ --qualifier BLUE \ --provisioned-concurrent-executions 100
Serverless
serverless.com › blog › aws-lambda-provisioned-concurrency
Provisioned Concurrency: What it is and how to use it with the Serverless Framework
Of course, we don’t really want to dip into the console if our service is built with the Serverless Framework, so instead, we can change one setting on our functions definition to add provisioned concurrency to that function. functions: hello: handler: handler.hello events: - http: path: /hello method: get provisionedConcurrency: 5 · In the example above, the hello Lambda function will always have 5 warm instances ready to go to handle incoming HTTP requests from API Gateway.
Videos
AWS
aws.amazon.com › blogs › aws › new-provisioned-concurrency-for-lambda-functions
New – Provisioned Concurrency for Lambda Functions | Amazon Web Services
November 3, 2022 - As more mission critical applications ... we are launching Provisioned Concurrency, a feature that keeps functions initialized and hyper-ready to respond in double-digit milliseconds....
Reddit
reddit.com › r/aws › lambda provisioned concurrency
r/aws on Reddit: Lambda provisioned concurrency
July 3, 2023 -
Hey, I'm a huge serverless user, I've built several applications on top of Lambda, Dynamo, S3, EFS, SQS, etc.
But I have never understood why would someone use Provisioned Concurrency, do you know a real use case for this feature?
I mean, if your application is suffering due to cold starts, you can just use the old-school EventBridge ping option and it costs 0, or if you have a critical latency requirement you can just go to Fargate instead of paying for provisioned concurrency, am I wrong?
Top answer 1 of 5
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pings won't save you from cold starts. if the workload just crosses what the current capacity can handle, a new instance will be warmed up. you have no control over whether it will be a ping or an actual user. pinging works as long as one single instance can serve all demands. fargate requires 24/7 running tasks, because the startup times are even worse than lambda's. if you want 24/7 running tasks together with scaling and all, sure, do that, but it requires a whole lot more setup.
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I mean, if your application is suffering due to cold starts, you can just use the old-school EventBridge ping option and it costs 0 This isn't nearly as effective as there's no real way to make EventBridge keep 100 or 1000 or more environments warm. If you have a very low traffic application maybe this method still makes sense, but for anything else PC is going to be more reliable
Dashbird
dashbird.io › home › knowledge base › aws lambda › provisioned concurrency
AWS Lambda Provisioned Concurrency | Dashbird
June 29, 2021 - With the AWS CLI, we can add, list and delete provisioned resources to our functions. Please see examples below: Add 50 as the concurrency level for the version 123 of my-function: aws lambda put-provisioned-concurrency --function-name my-function --qualifier 123 --provisioned-concurrent-executions 50
Lumigo
lumigo.io › home › aws lambda provisioned concurrency: the end of cold starts
AWS Lambda Provisioned Concurrency: The End of Cold Starts - Lumigo
June 25, 2024 - When functions are invoked, Lambda requires a ready supply of containers. This means functions are kept warm for only a limited amount of time after executing – typically 30-45 minutes – before being spun down. ... Once enabled, Provisioned Concurrency will keep your desired number of concurrent executions initialized and ready to respond to requests.
Medium
aws.plainenglish.io › what-is-provisioned-concurrency-and-when-should-you-use-it-6eab44e9cd46
What is Provisioned Concurrency- and When Should You Use It? | by Joseph Schambach | AWS in Plain English
June 2, 2025 - Reduce cold start latency in Lambda functions. ... TL;DR: Provisioned Concurrency keeps your AWS Lambda functions “warm,” eliminating cold start delays. This article explains what it is, when to use it (hint: latency-sensitive APIs), and how to set it up using versions or aliases — all with real examples and screenshots.
Amazon Web Services
docs.aws.amazon.com › aws lambda › developer guide › understanding lambda function scaling › configuring reserved concurrency for a function
Configuring reserved concurrency for a function - AWS Lambda
Reserved concurrency acts as both ... a function incurs no additional charges. Provisioned concurrency – This is the number of pre-initialized execution environments allocated to your function....
Quintagroup
quintagroup.com › blog › aws-lambda-provisioned-concurrency
AWS Lambda: Why Provisioned Concurrency is better than On-Demand Lambda — Quintagroup
June 1, 2023 - What does it do? It minimizes the estimate of cold starts by generating execution environments ahead of usage completely up to running the initialization code. It reduces the time spent on APIs invocations tremendously.
Top answer 1 of 6
1
To summarise:
- It's correct that you can't have provisioned concurrency for $LATEST.
- You need to publish new versions after each update.
- You can create an alias, which you need to update to refer to the newest published version each time.
- The alias can have provisioned concurrency.
- In API Gateway, you can paste the ARN of the alias in the integration target. (You may also be able to type lambda-name:alias, but I've not tried that.)
Thanks for the comments everyone.
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Thanks for the answers everyone.
I've just noticed that in the "create alias" form, I appear to be able to create an alias that refers to $LATEST. If I do this, will I be able to configure provisioned concurrency for that alias? Will it continue to refer to the new $LATEST when I upload a new version?
Ran The Builder
ranthebuilder.cloud › post › optimize-aws-lambda-with-dynamic-provisioned-concurrency
Optimize AWS Lambda with Dynamic Provisioned Concurrency
July 8, 2024 - Provisioned concurrency ensures that multiple Lambda functions remain ‘warm’, meaning they are initialized and prepared to respond promptly, unlike on-demand Lambda, which initializes resources upon invocation. Pre-initializing an environment includes tasks such as code download, environment setup, and running initialization code.
Trend Micro
trendmicro.com › cloudoneconformity › knowledge-base › aws › Lambda › enable-provisioned-concurrency.html
Enable and Configure Provisioned Concurrency | Trend Micro
March 13, 2024 - Provisioned concurrency runs continuously and has a separate pricing plan for concurrency and execution duration. This rule can help you work with the AWS Well-Architected Framework. ... When you are using Lambda functions for your serverless application, you are not provisioning hardware or ...
IT Labs
it-labs.com › high performing team › provisioned concurrency for aws lambda functions
Provisioned Concurrency for AWS Lambda functions - IT Labs
October 21, 2024 - However, AWS has heard the concerns and has provided the means to solve the problem. AWS in 2019 announced Provisioned Concurrency, a feature that allow Lambda customers to not have to worry about cold starts anymore.
Amazon Web Services
docs.aws.amazon.com › aws lambda › developer guide › understanding lambda function scaling
Understanding Lambda function scaling - AWS Lambda
For each concurrent request, Lambda provisions a separate instance of your execution environment. As your functions receive more requests, Lambda automatically handles scaling the number of execution environments until you reach your account's concurrency limit.
Pulumi
pulumi.com › home › blog › provisioned concurrency: avoiding cold starts in aws lambda
Provisioned Concurrency: Avoiding Cold Starts in AWS Lambda | Pulumi Blog
March 19, 2025 - Therefore, I set the publish attribute of my Lambda to true and reference a specific version of the Lambda in provisioning. A fixed level of provisioned concurrency works well for stable workloads.
Lumigo
lumigo.io › guides › aws lambda performance optimization › aws lambda concurrency
AWS Lambda Concurrency - Lumigo
August 21, 2024 - ... Provisioned concurrency lets you define a required amount of concurrency and pre-prepare the necessary containers, enabling your Lambda function to immediately run and respond to requests – with no cold starts.
Medium
rajaswalavalkar.medium.com › aws-lambda-reserved-concurrency-v-s-provisioned-concurrency-scaling-db8e93703b02
AWS Lambda Reserved Concurrency v/s Provisioned Concurrency Scaling | by Rajas Walavalkar | Medium
January 4, 2022 - When a function has being with a reserved concurrency configuration then no other lambda function within the same AWS account and region can use that concurrency. There is no charge for configuring reserved concurrency for a function. Provisioned concurrency — This concurrency initializes a requested number of execution environments so that they are prepared to respond immediately to your function’s invocations.
DEV Community
dev.to › aws-builders › provisioned-concurrency-reduce-cold-starts-in-aws-lambda-functions-part-1-4mob
Provisioned Concurrency - Reduce Cold Starts in AWS Lambda Functions Part 1 - DEV Community
March 13, 2024 - We may end up with a higher cost ... something on demand. Provisioned concurrency works in conjunction with Lambda versions instead of using the $LATEST code as we usually do....
Orchestra
getorchestra.io › guides › configuring-provisioned-concurrency-in-aws-lambda
Configuring provisioned concurrency in AWS lambda | Orchestra
September 9, 2024 - Provisioned concurrency keeps a specified number of function instances initialized and ready to respond immediately to requests, eliminating cold starts and ensuring a predictable response time.
Awsbites
awsbites.com › 129-lambda-provisioned-concurrency
Lambda Provisioned Concurrency
In this episode, we discuss AWS Lambda provisioned concurrency. We start with a recap of Lambda cold starts and the different concurrency control options. We then explain how provisioned concurrency works to initialize execution environments in advance to avoid cold starts.