A distributed analytics engine runs 12 EC2 instances in one Availability Zone. The nodes exchange thousands of tiny messages per second and must keep jitter as low as possible. The current design launches the instances across multiple placement groups and uses general-purpose burstable instances. Which two changes will most directly lower east-west network latency and variability? Select two.

Spread the instances across three Availability Zones for better fault tolerance.

Spreading across AZs improves resilience, but it increases network distance and typically adds latency. The scenario is explicitly about minimizing jitter and latency for frequent east-west traffic within one AZ, so multi-AZ spread is the wrong optimization.

Front the nodes with an Application Load Balancer to balance the internal messages.

An ALB is for HTTP/HTTPS application traffic, not for direct node-to-node messaging performance. It adds a layer that does not solve the underlying east-west latency issue. The workload needs closer physical placement and better networking, not a web load balancer.

Store the messages on EBS volumes so the nodes avoid network communication.

EBS is block storage for persistent data, not a low-latency message bus. Writing messages to disk would add storage latency and does not create efficient inter-node communication. It also changes the workload architecture in an unsupported way for this requirement.

What does this SAA-C03 question test?

Read the scenario before looking for a memorised answer.

What is the correct answer to this question?

The correct answer is: Move all instances into a cluster placement group. — For chatty EC2 clusters, the two strongest improvements are a cluster placement group and higher-network-bandwidth instance families. The placement group reduces physical and network distance between nodes, while the instance type choice increases packet-handling capacity and reduces congestion effects. Together, they lower both average latency and jitter, which is exactly what a tiny-message distributed engine needs. Spreading instances across AZs improves fault isolation but hurts latency. An ALB is not a tuning tool for east-west binary messaging. EBS is durable block storage, not a substitute for inter-node transport. The scenario is about reducing network delay and variability, so architecture choices that add layers or distance are counterproductive.

What should I do if I get this SAA-C03 question wrong?

Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.