SAA-C03 Design High-Performing Architectures Practice Test 4 — 15 Questions

Question 1

A marketing site serves versioned JavaScript and CSS from an Amazon S3 origin through Amazon CloudFront. After each release, the cache hit ratio drops sharply because clients keep sending request headers and query strings that are not needed for asset retrieval. Which two changes should improve cache efficiency the most? Select two.

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Create a CloudFront cache policy that excludes unnecessary headers, query strings, and cookies from the cache key.. CloudFront cache policies allow you to explicitly control which headers, query strings, and cookies are included in the cache key. By excluding unnecessary ones (e.g., User-Agent, random query parameters), you prevent cache fragmentation and ensure that identical assets served with different request metadata map to the same cached object, dramatically improving the cache hit ratio.

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Move the S3 origin behind an Application Load Balancer so CloudFront can cache responses more effectively.

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Store the objects in Amazon S3 Standard-IA so repeated requests are cheaper.

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Lower the CloudFront TTL to zero so viewers always receive the newest content immediately.

Question 2

A single EC2 instance hosts a low-latency database cache that writes a large random working set to block storage. The application needs sustained high IOPS and low latency, and the storage must remain attached to the instance while it runs. Which two design choices best meet the requirement? Select two.

Accepted Answer

Use an io2 Block Express EBS volume for the highest sustained IOPS and low-latency performance.. Io2 Block Express EBS volumes are designed for mission-critical workloads requiring sustained high IOPS and low latency. They offer up to 256,000 IOPS per volume with sub-millisecond latency, making them ideal for a low-latency database cache that writes a large random working set to block storage. The storage remains attached to the EC2 instance while it runs, meeting the requirement for persistent block-level storage.

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Use an S3 bucket as the backing store because object storage scales automatically.

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Choose a cold HDD-based volume so the cache has durable low-cost storage.

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Use the root volume from a T-series instance because burst credits can absorb the write spikes.

Question 3

Based on the exhibit, a retail analytics service repeatedly reads the same DynamoDB items during an active campaign. The business can tolerate data that is a few seconds stale, but the application must minimize latency and reduce pressure on DynamoDB. A load test shows that 80% of reads target only 200 item keys. What should the solutions architect implement?

Accepted Answer

Add a DynamoDB Accelerator (DAX) cluster in front of the table and point the application to the DAX endpoint.. DynamoDB Accelerator (DAX) is a fully managed, highly available, in-memory cache designed specifically for DynamoDB. It reduces read latency from single-digit milliseconds to microseconds and offloads repeated reads from the table, which directly addresses the requirement to minimize latency and reduce pressure on DynamoDB. Since the business can tolerate stale data (DAX default TTL is 5 minutes, but can be configured lower), DAX is ideal for the 80% of reads hitting only 200 hot keys.

Answer

Switch the table to provisioned capacity with auto scaling so DynamoDB can handle the repeated reads more efficiently.

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Create a global table in a second Region and read from the replica Region to lower latency.

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Move the hot items into Amazon ElastiCache for Redis and keep the remaining data in DynamoDB.

Question 4

Based on the exhibit, a trading platform exposes a custom binary TCP protocol to partner systems. The service must preserve the original client source IP for rate limiting, support TLS pass-through to the application, and minimize network latency. The team also wants a simple architecture that can scale across multiple Availability Zones. What load balancing option should the solutions architect choose?

Accepted Answer

Network Load Balancer with TCP listeners and target groups in the private subnets.. A Network Load Balancer (NLB) with TCP listeners is the correct choice because it preserves the original client source IP address (via the Proxy Protocol header or direct preservation in the TCP flow), supports TLS pass-through (no decryption at the load balancer), and minimizes latency by operating at Layer 4. It also scales across multiple Availability Zones with simple target groups in private subnets, meeting all stated requirements.

Answer

Application Load Balancer with path-based routing and HTTP/2 enabled.

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Amazon API Gateway REST API integrated directly with the EC2 instances.

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CloudFront in front of the EC2 instances to cache and terminate the client connections.

Question 5

Based on the exhibit, a low-latency analytics platform runs 10 EC2 instances in the same Availability Zone. The nodes exchange a very high volume of east-west messages and must experience the lowest possible network latency and jitter. A separate operations team also wants to reduce the risk that all nodes land on the same physical hardware rack. Which placement strategy should the solutions architect use?

Accepted Answer

Cluster placement group. A cluster placement group is the correct choice because it provides the lowest possible network latency and jitter by ensuring all 10 EC2 instances are placed in close proximity within a single Availability Zone, enabling non-blocking, high-bandwidth communication. This is ideal for high-volume east-west traffic, as it maximizes network performance for tightly coupled workloads like analytics platforms.

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Spread placement group

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Partition placement group

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Auto Scaling group with a mixed instances policy

Question 6

A media company serves versioned JavaScript and CSS files from an Amazon S3 origin through CloudFront. After each release, origin requests spike even though the files are public. Browser requests include a tracking cookie, an Authorization header, and a cache-busting query string that the site no longer needs. Which three changes will most improve the CloudFront cache hit ratio without exposing private content? Select three.

Accepted Answer

Rename each static asset with a content hash or release version in the filename before publishing.. Renaming static assets with a content hash or version in the filename ensures that each new release creates a unique object key in S3. This allows CloudFront to treat the new file as a distinct object, avoiding cache invalidation issues and enabling long-term caching of the old version. Without this, even with cache-busting query strings, CloudFront might still serve stale content or require frequent invalidations, reducing the cache hit ratio.

Answer

Enable CloudFront compression and configure the origin to return Cache-Control: no-store for all files.

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Forward all viewer headers to the origin so CloudFront can personalize every request.

Question 7

A latency-sensitive mobile game backend uploads large files to S3 from users around the world. Which two features can improve upload performance?

Accepted Answer

S3 multipart upload. S3 multipart upload is correct because it allows large files to be uploaded in parallel parts, which reduces the impact of network latency and improves throughput. For a latency-sensitive mobile game backend, this feature enables faster uploads by splitting the file into smaller chunks that can be uploaded concurrently, even over unstable connections.

Answer

S3 Object Lock

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S3 Inventory

Question 8

A Lambda-based travel booking site has unpredictable traffic spikes and users see latency caused by cold starts. The function must respond consistently during expected campaign windows. What should be configured?

Accepted Answer

Provisioned concurrency during campaign windows. Provisioned concurrency initializes a specified number of execution environments in advance, eliminating cold starts for those instances. During campaign windows, this ensures consistent sub‑millisecond latency because the function is always warm and ready to handle requests immediately.

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A larger deployment package

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CloudTrail data events

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Reserved concurrency only

Question 9

A read-heavy media archive repeatedly queries the same product catalogue data from DynamoDB with millisecond latency requirements. Which service can reduce read latency and table load?

Accepted Answer

DynamoDB Accelerator (DAX). DynamoDB Accelerator (DAX) is a fully managed, in-memory cache for DynamoDB that delivers up to 10x read performance improvement by reducing response times from single-digit milliseconds to microseconds. For a read-heavy workload repeatedly querying the same product catalogue data, DAX caches the hot items, offloading read requests from the DynamoDB table and significantly reducing table read capacity consumption.

Answer

Amazon Kinesis Data Firehose

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AWS Glue Data Catalog

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S3 Transfer Acceleration

Question 10

A analytics dashboard uses RDS MySQL and receives many read-only reporting queries that slow down the primary database. What should the architect add? The design must avoid adding custom operational scripts.

Accepted Answer

RDS read replica and route reporting queries to it. RDS read replicas are designed specifically to offload read-heavy workloads from the primary DB instance. By routing reporting queries to a read replica, the primary database is freed from processing those queries, reducing contention and improving overall performance. This approach requires no custom scripts—AWS handles replication automatically.

Answer

S3 lifecycle policy

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Multi-AZ standby and route reads to the standby

Answer

A larger NAT gateway

Question 11

A latency-sensitive mobile game backend uploads large files to S3 from users around the world. Which two features can improve upload performance? The design must avoid adding custom operational scripts.

Accepted Answer

S3 multipart upload. S3 multipart upload is correct because it allows large files to be uploaded in parallel parts, significantly reducing the impact of latency and packet loss over long distances. This feature is built into S3 and requires no custom scripts, making it ideal for a latency-sensitive mobile game backend.

Answer

S3 Object Lock

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S3 Inventory

Question 12

A Lambda-based travel booking site has unpredictable traffic spikes and users see latency caused by cold starts. The function must respond consistently during expected campaign windows. What should be configured? The design must avoid adding custom operational scripts.

Accepted Answer

Provisioned concurrency during campaign windows. Provisioned concurrency keeps a specified number of Lambda execution environments initialized and ready to respond immediately, eliminating cold starts. By enabling it only during campaign windows, you ensure consistent latency for the travel booking site during traffic spikes without incurring cost during off-peak periods. This directly addresses the requirement to avoid custom scripts, as it is a native AWS feature configured via the Lambda API or console.

Answer

A larger deployment package

Answer

CloudTrail data events

Answer

Reserved concurrency only

Question 13

A read-heavy media archive repeatedly queries the same product catalogue data from DynamoDB with millisecond latency requirements. Which service can reduce read latency and table load? The design must avoid adding custom operational scripts.

Accepted Answer

DynamoDB Accelerator (DAX). DynamoDB Accelerator (DAX) is an in-memory cache for DynamoDB that delivers microsecond read latency, reducing the load on the underlying DynamoDB tables by serving repeated queries from its cache. This directly addresses the read-heavy media archive's millisecond latency requirements without requiring custom operational scripts, as DAX is fully managed and integrates seamlessly with existing DynamoDB API calls.

Answer

Amazon Kinesis Data Firehose

Answer

AWS Glue Data Catalog

Answer

S3 Transfer Acceleration

Question 14

A telemetry pipeline uses RDS MySQL and receives many read-only reporting queries that slow down the primary database. What should the architect add? The design must avoid adding custom operational scripts.

Accepted Answer

RDS read replica and route reporting queries to it. RDS Read Replicas are designed specifically to offload read-heavy workloads from the primary database. By creating a read replica and routing reporting queries to it, the architect reduces load on the primary MySQL instance without custom scripts. This is a native, managed feature of RDS that supports asynchronous replication.

Answer

Multi-AZ standby and route reads to the standby

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S3 lifecycle policy

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A larger NAT gateway

Question 15

A document portal requires consistent high IOPS for a transactional database on EC2. Which EBS volume type is most suitable? The design must avoid adding custom operational scripts.

Accepted Answer

Provisioned IOPS SSD such as io2. Provisioned IOPS SSD volumes (io2) are designed for latency-sensitive transactional workloads that require consistent, high IOPS. They deliver a predictable performance level with a 99.9% durability guarantee, making them ideal for a database on EC2 without needing custom scripts to manage performance.

Answer

sc1 Cold HDD

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Instance store only

Answer

st1 Throughput Optimized HDD