A research team runs a latency-sensitive distributed training job on Amazon EC2. They deploy 80 identical nodes that exchange small messages frequently and need low network jitter. The job must run entirely within one Availability Zone. Which placement group strategy should a solutions architect use to maximize intra-cluster network performance?

Use a spread placement group to distribute instances across distinct hardware to reduce jitter.

Spread placement groups are designed primarily for fault isolation by placing instances across distinct underlying hardware. They do not prioritize the tight placement needed to maximize low-jitter, low-latency networking between all nodes.

Use a partition placement group and place each node into its own partition for uniform latency.

Partition placement groups provide isolation between partitions for very large deployments, limiting blast radius. They are not the best choice for maximizing low-jitter network performance among every node that must communicate constantly within a single AZ.

Do not use a placement group; rely on the default EC2 scheduling to balance latency and availability.

Without a placement group, instance placement is left to default scheduling, which can vary across different underlying hardware. That unpredictability makes it harder to achieve consistently low network jitter for tightly coupled, frequent-message communication.

What does this SAA-C03 question test?

Static NAT maps one inside address to one outside address.

What is the correct answer to this question?

The correct answer is: Use a cluster placement group to keep all instances in close proximity within the same Availability Zone. — Use a cluster placement group. Cluster placement groups are optimized for high network throughput and low latency/jitter between instances placed close together, and they are scoped to a single Availability Zone—matching the requirement that all 80 nodes run in one AZ and exchange small messages frequently. Spread focuses on fault isolation, and partition focuses on scaling/isolating very large clusters across partitions, neither of which directly optimizes for maximum intra-cluster low jitter across all nodes. Why others are wrong: Spread placement groups primarily optimize for failure-domain separation rather than the tight physical locality that reduces jitter for continuously communicating nodes. Partition placement groups are intended for large-scale isolation patterns and do not guarantee the lowest-jitter communication across the entire set of nodes. Not using a placement group removes locality guarantees, so default placement can increase variability in network performance for latency-sensitive workloads.

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.