Examkin

Soru

Zorluk: OrtaServerless Development with AWS Lambda

A serverless application contains multiple AWS Lambda functions. During peak traffic periods, a background data-processing function triggered by Amazon S3 events scales rapidly and consumes all of the available execution concurrency in the AWS Region. This causes customer-facing Lambda functions integrated with Amazon API Gateway to fail with throttling errors. Which configuration should a developer apply to prevent the background function from exhausting the available regional concurrency?

  1. A
    Enable provisioned concurrency on the customer-facing API Gateway-triggered Lambda functions.
  2. B
    Configure an Amazon SQS queue between S3 and the background function, and set the queue's visibility timeout to zero.
  3. Configure a reserved concurrency limit on the background data-processing Lambda function.Cevap
  4. D
    Attach a resource-based policy to the S3 bucket that limits the invocation rate of the background Lambda function.

Cevap

Configure a reserved concurrency limit on the background data-processing Lambda function.
The correct answer is to configure a reserved concurrency limit on the background data-processing Lambda function. Setting a reserved concurrency limit on a Lambda function acts as a maximum concurrency cap (preventing it from scaling beyond that number and exhausting the region's shared unreserved pool) and also guarantees that the specified concurrency is dedicated to that function.

Adım Adım Çözüm

1
Analyze the cause of the throttling error.
The background data-processing Lambda function is scaling excessively and consuming all regional unreserved concurrency, leaving no execution capacity for other functions.
AWS Lambda pools concurrency region-wide by default, meaning a high-scale function can starve other functions of execution slots.
2
Evaluate options for limiting concurrency consumption of a specific function.
Reserved concurrency allows developers to define a hard limit on the concurrency of a specific Lambda function.
By setting a reserved concurrency limit, the function cannot scale past that limit, thereby protecting the shared unreserved concurrency pool.
3
Differentiate reserved concurrency from provisioned concurrency.
Reserved concurrency acts as a ceiling to limit scale-out, whereas provisioned concurrency keeps environments warm and ready for expected load but does not cap execution growth.
Choosing reserved concurrency directly solves the problem of background function over-scaling.

Anahtar Kavram

Managing concurrency in AWS Lambda to prevent account-level resource starvation.
Bu soruyu puanla

Konular

Serverless Development with AWS Lambda

Bu konudan daha fazla soru