5 exercises on serverless architecture vocabulary.
0 / 5 completed
1 / 5
What is a cold start in AWS Lambda?
Cold start: Lambda execution environment lifecycle: Init (allocate micro-VM, download package, start runtime, run global code) → Invoke (call handler) → Shutdown (after idle timeout). Cold starts add 100ms-3s depending on runtime and package size. Java/JVM runtimes are the worst (heavy startup). Node.js/Python are fastest. Mitigations: provisioned concurrency (pre-warmed environments), smaller packages (tree-shaking), move init code outside the handler to cache across warm invocations.
2 / 5
What is the difference between synchronous and asynchronous Lambda invocation?
Synchronous: caller waits for response. Error propagates to caller — the caller must implement retries. Triggers: API Gateway, ALB, SDK direct invoke, Lambda Function URL. Asynchronous: Lambda queues the event internally, returns 202. Retries: 2 automatic retries on failure. After retries exhausted: DLQ (SQS/SNS) or Lambda Destination. Triggers: S3, SNS, EventBridge. Polling (event source mapping): Lambda polls the source. Triggers: SQS, Kinesis, DynamoDB Streams. Failed SQS batches go to DLQ.
3 / 5
What does reserved concurrency do in Lambda?
Reserved concurrency: carves N units from the account pool (default 1,000/region). Dual effect: (1) guarantees at least N concurrent executions for this function; (2) caps the function at N — throttles excess requests with 429. Setting reserved=0 disables the function. No extra cost. Provisioned concurrency (different): pre-initializes N environments, eliminating cold starts for up to N concurrent requests. Has cost even when idle. Combine: reserve=100, provision=20 means 100 maximum, 20 always warm.
4 / 5
What is the fan-out pattern in serverless architectures?
Fan-out: one event triggers multiple parallel downstream processes. Implementation: Lambda → SNS topic → multiple SQS queues (each consumed by a different Lambda). Or Lambda → EventBridge → content-based routing to different targets. Benefits: parallel processing (inventory check, fraud detection, and notification all run simultaneously), decoupling, independent scaling of each downstream process. Step Functions Map state: parallel branches in a workflow — a managed fan-out with built-in error handling and state tracking.
5 / 5
Why must serverless functions be stateless?
Stateless design: each invocation should be self-contained. In-memory data MAY persist within the same environment across sequential invocations on the same container (used for connection caching). But: Lambda may spin up a new environment at any time; concurrent invocations each have their own environment. State belongs externally: DynamoDB (application state), S3 (files/objects), ElastiCache (caching), SQS (work queues), Step Functions (workflow state). /tmp: 512MB–10GB ephemeral — reliable within one environment lifetime, not shared.
What does the "Serverless Architecture Patterns" vocabulary exercise cover?
This exercise tests real IT vocabulary related to serverless architecture patterns through 5 multiple-choice questions, each built from realistic workplace sentences rather than abstract definitions.
Is this vocabulary exercise free to use?
Yes. Every exercise on CoderSlingo, including this one, is completely free — no account, sign-up, or payment required.
How many questions does this exercise have?
This exercise has 5 questions. Each one shows a real-world sentence or scenario with multiple-choice options and an explanation once you answer.
What happens after I answer a question?
You'll see immediate feedback showing whether your answer was correct, along with a short explanation of why — then a button to move to the next question, and a full results screen at the end.
Can I retry the exercise if I get questions wrong?
Yes. Once you reach the results screen, click "Try again" to reset your answers and go through the exercise from the start as many times as you like.
Do I need to create an account to take this exercise?
No account is needed. Your answers are scored in your browser during the session — nothing is saved to a server, so you can jump straight in.
Is my progress saved if I leave the page?
No — progress within an exercise resets if you navigate away or reload. Each exercise is short enough to complete in a few minutes in one sitting.
Are these vocabulary exercises connected to other topics?
Yes — browse the full vocabulary exercises hub to find related modules covering adjacent IT topics and roles.
How is this different from reading a glossary or blog article?
Exercises like this one are active recall drills — you have to choose the correct term or phrasing yourself, which builds retention faster than passively reading a definition.
Where can I find more vocabulary exercises?
Browse the full Vocabulary exercises hub for hundreds of modules covering Agile, DevOps, security, databases, architecture, and more — organised by IT role and skill.