SAP-C02 Continuous Improvement for Existing Solutions Practice Question

A company is using AWS Lambda functions to process data from an S3 bucket. Recently, the function has been timing out. The function has a 5-minute timeout configured. What is the most likely cause of the timeout?

⚠ Common exam trap

SAP-C02 often tests the distinction between timeout and throttling; candidates may confuse concurrency limits with execution time, or overlook that memory affects performance but is not the direct cause of timeout when file size increases.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

The Lambda function is processing larger files than before.

The most likely cause of the timeout is that the Lambda function is processing larger files than before. Lambda timeout is the maximum execution time, and if the function takes longer than the configured 5 minutes due to increased processing time (e.g., larger files), it will time out. Other options like VPC change, concurrency, or memory are less directly related to timeout duration.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
The Lambda function was moved to a different VPC.
Why it's wrong here
Moving a function into a VPC only causes timeouts if it then lacks NAT or endpoint access to S3; the move alone is not the cause. VPC placement is relevant when diagnosing connectivity failures, not general execution duration.
✗
The Lambda function's reserved concurrency is set too low.
Why it's wrong here
Reserved concurrency limits how many invocations run simultaneously; excess requests are throttled or queued, producing throttling errors rather than a single invocation exceeding its 5-minute timeout. Reserved concurrency is used to cap blast radius or guarantee capacity for critical functions.
✗
The Lambda function's memory is too low.
Why it's wrong here
Insufficient memory reduces allocated CPU proportionally, slowing execution, but a 5-minute timeout on S3-triggered processing usually indicates the function is waiting on a network resource. Memory tuning is correct when CPU-bound work runs slowly, not when calls hang.
✓
The Lambda function is processing larger files than before.
Why this is correct
Larger files increase the time spent reading and processing within the same invocation, so execution duration grows until it exceeds the configured 5-minute limit. The timeout is a symptom of longer processing, not of memory, permissions or concurrency settings.

Quick reference

AWS S3 Storage Class Comparison

Storage Class	Min Duration	Retrieval	Use Case
S3 Standard	None	Immediate	Frequently accessed data
S3 Standard-IA	30 days	Immediate	Infrequent access, rapid retrieval
S3 One Zone-IA	30 days	Immediate	Non-critical infrequent data
S3 Intelligent-Tiering	None	Immediate–hours	Unknown or changing access patterns
S3 Glacier Instant	90 days	Milliseconds	Archive with instant retrieval
S3 Glacier Flexible	90 days	Minutes–hours	Archive, flexible retrieval
S3 Glacier Deep Archive	180 days	Hours	Long-term compliance archive

Go deeper

SAP-C02 Continuous Improvement for Existing Solutions Practice Question

Why each option matters

Option-by-option breakdown

AWS S3 Storage Class Comparison

Related to this question