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
In Lambda, concurrency is the number of in-flight requests that your function is currently handling. There are two types of concurrency controls available: Reserved concurrency – This sets both the maximum and minimum number of concurrent instances allocated to your function.
Amazon Web Services
docs.aws.amazon.com › aws lambda › developer guide › understanding lambda function scaling
Understanding Lambda function scaling - AWS Lambda
By default, Lambda provides your account with a total concurrency limit of 1,000 concurrent executions across all functions in an AWS Region. To support your specific account needs, you can request a quota increase · and configure function-level concurrency controls so that your critical functions ...
Setting reserved concurrency limit - Serverless Framework - Serverless Forums
I’m fairly new to using the serverless framework. Setting the reserved concurrency on a function would reflect the same when I check on the lambda console. But, if I set the reserved concurrency in the providers section of serverless.yml, I don’t see the reserved concurrency being set. More on forum.serverless.com
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August 14, 2019AWS Lambda Reserved Concurrency
no, it is not possible. lambda instances don't know about each other. it has to be something about sqs visibility timeout, and some error in signaling the processing of messages. More on reddit.com
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December 27, 2024🤡Lambda throttling and retries are killing me!!
If your reserved concurrency is set to 1 (a limit of 1) then any invocation requests that come in during an execution will be throttled - that’s the intended behaviour you’ve configured. Remember that CloudWatch doesn’t sample or aggregate per millisecond so having 12 invocations during a sampling window doesn’t seem unusual. Take a look at your function logs and the execution duration for function invokes. If what you want to achieve is the ability to have events processed asynchronously by no more than 1 Lambda function I’d encourage you to take a look at the queueing / poller pattern using SQS. SQS now has settings to help limit Lambda concurrency so you don’t need to use reserved concurrency. Have a read of this one to see if it’s helpful: https://aws.amazon.com/blogs/compute/introducing-maximum-concurrency-of-aws-lambda-functions-when-using-amazon-sqs-as-an-event-source/ In other words…. your producer (the system “asking” Lambda to do work) would write a message on to the SQS queue instead of directly asynchronously invoking Lambda. The SQS queue (with Lambda concurrency settings) would be wired up to your function and do what it looks like you’re trying to achieve. More on reddit.com
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April 29, 2024API Gateway + Lambda Function concurrency and cold start issues
> I'm also using the default memory of 128MB. Is that too low? Cpu is proportionnal to memory for lambdas, so yes, even if you do not need more memory, configuring more of if with increase the available cpu and make the responses faster. ( and so it will also lower your concurrency , which will sove another problem you have ) More on reddit.com
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October 6, 2023Videos
iCompaas Support
support.icompaas.com › support › solutions › articles › 62000218450-ensure-lambda-concurrency-limit-is-configured
Ensure Lambda Concurrency Limit is Configured : iCompaas Support
March 31, 2023 - The functions cannot scale out ... you can reserve concurrency to prevent your function from using all the available concurrency in the Region, or from overloading downstream resources....
Trend Micro
trendmicro.com › cloudoneconformity › knowledge-base › aws › Lambda › lambda-function-reserved-concurrency.html
Enable and Configure Reserved Concurrency | Trend Micro
November 17, 2023 - 06 On the Edit concurrency configuration page, select Reserve concurrency under Concurrency, and enter the amount of concurrency to reserve for the selected Lambda function. Choose Save to apply the configuration changes. 07 Repeat steps no. 4 – 6 for each Amazon Lambda function that you ...
Substack
urielbitton.substack.com › p › using-reserved-vs-unreserved-concurrency
Using Reserved Vs Unreserved Concurrency in AWS Lambda
June 26, 2025 - When a function uses unreserved concurrency it can use up as much as it needs from the pool of total concurrency and starve other functions. Reserved concurrency on the other hand guarantees your function always has a set number of concurrency.
Orchestra
getorchestra.io › guides › configuring-reserved-concurrency-in-aws-lambda
Configuring reserved concurrency in AWS lambda | Orchestra
September 9, 2024 - By default, Lambda can scale automatically, up to a soft limit (which varies by account and region). Reserved concurrency is a configuration setting that allows you to specify the maximum number of concurrent executions for a Lambda function.
DEV Community
dev.to › prajwalnayak › concurrency-and-autoscaling-in-aws-lambda-3319
Concurrency and Autoscaling in AWS Lambda - DEV Community
February 16, 2025 - Types of Concurrency Unreserved ... Lambda functions in the account. Reserved Concurrency Guarantees a fixed number of concurrent executions for a specific function....
Amazon Web Services
docs.aws.amazon.com › aws lambda › api reference › data types › concurrency
Concurrency - AWS Lambda
The number of concurrent executions that are reserved for this function. For more information, see Managing Lambda reserved concurrency. ... Valid Range: Minimum value of 0. ... For more information about using this API in one of the language-specific AWS SDKs, see the following:
Amazon Web Services
docs.aws.amazon.com › aws lambda › api reference › actions › getfunctionconcurrency
GetFunctionConcurrency - AWS Lambda
Returns details about the reserved concurrency configuration for a function. To set a concurrency limit for a function, use PutFunctionConcurrency. GET /2019-09-30/functions/FunctionName/concurrency HTTP/1.1 · The request uses the following URI parameters. ... The name or ARN of the Lambda function. Function name – my-function. Function ARN – arn:aws...
Serverless
serverless.com › framework › docs › providers › aws › guide › functions
Serverless Framework - AWS Lambda Functions | Serverless Framework
How to configure AWS Lambda functions in the Serverless Framework
Serverlessland
assets.serverlessland.com › pdf › SVS305+Understanding+AWS+Lambda+Concurrency.pdf pdf
Understanding AWS Lambda concurrency
December 1, 2022 - We cannot provide a description for this page right now
Serverless Forums
forum.serverless.com › serverless framework
Setting reserved concurrency limit - Serverless Framework - Serverless Forums
August 14, 2019 - I’m fairly new to using the serverless framework. Setting the reserved concurrency on a function would reflect the same when I check on the lambda console. But, if I set the reserved concurrency in the providers section …
Medium
beaudry-maxime.medium.com › aws-lambda-reserved-concurrency-vs-retry-24776ffc84bf
AWS Lambda Reserved Concurrency vs Retry | by Maxime Beaudry | Medium
April 16, 2021 - AWS Lambda Reserved Concurrency vs Retry When you configure an AWS Lambda, you can configure it to only allow a certain number of concurrent executions through the “Reserve concurrency” setting …
Symphonia
blog.symphonia.io › posts › 2017-12-13_aws-lambda-reserved-concurrency
AWS Lambda Reserved Concurrency | The Symphonium
January 6, 2020 - It limits the number of instances of your Lambda function that can be instantiated at any time to the value specified. It makes sure there is always at least enough concurrency capability available in the account to run the number of instances ...
The Burning Monk
theburningmonk.com › home › 3 ways to control concurrency in serverless applications
3 ways to control concurrency in serverless applications | theburningmonk.com
April 28, 2024 - With SNS FIFO, you can’t fan out messages to Lambda functions directly (see official documentation here [3]). This is why you always need to have SQS FIFO in the mix as well. Like Kinesis, event orders are preserved within a group and identified by the group ID in the messages. Recently, AWS introduced a max concurrency setting for SQS event sources (see here [4]). This solves the long-standing problem of using reserved concurrency for SQS functions.
Dd
dd.engineering › blog › concurrency-in-aws-lambda
Concurrency in AWS Lambda | DD.ENGINEERING
The number of concurrent function invocations is limited. All Lambda functions in the same AWS account and region share a single concurrency limit. By default the limit is 1000 concurrent invocations per region.
Medium
aws.plainenglish.io › aws-lambda-reserved-vs-provisioned-concurrency-choosing-the-right-strategy-676294bc7e74
AWS Lambda Reserved vs. Provisioned Concurrency: Choosing the Right Strategy | by Ekant Mate (AWS APN Ambassador) | AWS in Plain English
January 15, 2024 - AWS Lambda, Amazon Web Services’ serverless compute service, is a popular choice for running code without the need to manage servers. However, when it comes to managing the performance of your Lambda functions, you have two essential options: Reserved Concurrency and Provisioned Concurrency.
Sedai
sedai.io › blog › under-standing-aws-lambda-concurrency
AWS Lambda Concurrency Explained: Setup & Optimization | Sedai
Reserved concurrency in Lambda guarantees a specific number of concurrent instances allocated exclusively to a function. This ensures that high-priority or critical functions always have the necessary resources to handle incoming requests, even ...
KodeKloud Notes
notes.kodekloud.com › docs › AWS-Lambda › Advanced-Topics › Reserved-and-Unreserved-Concurrency
Reserved and Unreserved Concurrency - KodeKloud Notes
Managing concurrency in AWS Lambda ensures that high-priority functions always have the capacity they need. By default, your account’s unreserved concurrency sets a soft limit on total parallel executions. For mission-critical workloads, you can allocate reserved concurrency to specific functions.
AWS re:Post
repost.aws › knowledge-center › lambda-provisioned-reserved-concurrency
List Lambda functions with concurrency | AWS re:Post
April 30, 2024 - The code iterates through each Lambda function. The function calls the get_function_concurrency method to retrieve details about the reserved or provisioned concurrency configuration for each function in the specified AWS Region.