SOA-C02 Cost and Performance Optimization Practice Test 6 — 15 Questions

Question 1

A SysOps administrator manages a fleet of Amazon EC2 instances. The administrator needs to identify underutilized instances and receive recommendations for instance type changes to reduce costs. Which AWS service should be used to provide these rightsizing recommendations?

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

Accepted Answer

AWS Compute Optimizer. AWS Compute Optimizer is the correct service because it uses machine learning to analyze historical utilization metrics (CPU, memory, network, and storage) of EC2 instances and generates rightsizing recommendations, including instance type changes, to reduce costs and improve performance. It directly addresses the need to identify underutilized instances and provide actionable recommendations for cost optimization.

Answer

AWS Cost Explorer

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AWS Trusted Advisor

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Amazon CloudWatch Dashboard

Question 2

A company stores video files in Amazon S3. The files are accessed frequently for the first week, then weekly for the next month, and then rarely after that. The files must be retained for 5 years and any access must be served within minutes. The SysOps administrator needs to minimize storage costs while meeting these requirements. Which lifecycle policy configuration is the most cost-effective?

Accepted Answer

Transition to S3 Standard-IA after 7 days, then to S3 Glacier Instant Retrieval after 30 days.. It transitions to S3 Standard-IA after 7 days (matching the frequent first-week access), then to S3 Glacier Instant Retrieval after 30 days (matching the weekly access for the next month). Glacier Instant Retrieval provides millisecond retrieval for rarely accessed data, meeting the 'within minutes' requirement while minimizing costs compared to Standard-IA or Intelligent-Tiering.

Answer

Transition to S3 Standard-IA after 7 days, then to S3 Glacier Flexible Retrieval after 30 days.

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Transition to S3 One Zone-IA after 7 days, then to S3 Glacier Deep Archive after 30 days.

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Transition to S3 Intelligent-Tiering after 7 days.

Question 3

A company stores application logs in Amazon S3. The logs are rarely accessed after the first 30 days, but must be retained for 7 years for compliance. The SysOps administrator wants to minimize storage costs while ensuring logs are available for retrieval within 12 hours if needed. Which S3 lifecycle configuration is the most cost-effective?

Accepted Answer

S3 Standard for 30 days, then transition to S3 Glacier Deep Archive. It transitions logs from S3 Standard (for frequent access during the first 30 days) to S3 Glacier Deep Archive, which offers the lowest storage cost for long-term retention. Since logs must be retained for 7 years and only need retrieval within 12 hours, Glacier Deep Archive's 12-hour standard retrieval time meets the requirement while minimizing costs.

Answer

S3 Standard for 30 days, then transition to S3 Glacier (Flexible Retrieval)

Answer

Use S3 Intelligent-Tiering from the start

Answer

S3 Standard for 30 days, then transition to S3 One Zone-IA

Question 4

A company runs a web application on Amazon EC2 instances. The application's traffic pattern is unpredictable, often spiking to 3x normal load for short periods. The SysOps administrator needs to ensure that the application can handle spikes without performance degradation while minimizing costs. Which combination of purchasing options and scaling strategies should the administrator use?

Accepted Answer

Use a mix of Reserved Instances for baseline and On-Demand for spikes, with a target tracking scaling policy.. It combines Reserved Instances for the predictable baseline load, which reduces costs through a significant discount, with On-Demand Instances to handle unpredictable spikes. The target tracking scaling policy automatically adjusts capacity based on a target metric (e.g., average CPU utilization), ensuring performance is maintained during spikes without manual intervention or over-provisioning.

Answer

Use all Spot Instances with a simple scaling policy.

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Use all On-Demand Instances with a scheduled scaling policy.

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Use only Reserved Instances with a manual scaling policy.

Question 5

A company runs a web application on Amazon EC2 instances that have variable traffic patterns. The application experiences steady baseline traffic with occasional spikes. The SysOps administrator wants to optimize costs while ensuring performance during spikes. Which pricing model should be used for the baseline capacity and for the burst capacity?

Accepted Answer

Reserved Instances for baseline, Spot Instances for burst capacity. Reserved Instances provide a significant discount (up to 72%) over On-Demand for steady-state workloads, making them ideal for baseline capacity. Spot Instances offer the lowest cost (up to 90% discount) but can be interrupted with a 2-minute warning, which is acceptable for burst capacity that can tolerate interruptions or be designed to failover gracefully. This combination minimizes cost while ensuring the baseline always runs and burst capacity can be added during spikes.

Answer

On-Demand Instances for baseline, Reserved Instances for burst capacity

Answer

Spot Instances for baseline, On-Demand Instances for burst capacity

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Dedicated Hosts for baseline, Spot Instances for burst capacity

Question 6

A company runs a batch processing job every night on Amazon EC2 instances. The job takes exactly 2 hours to complete and can be interrupted and resumed later. The SysOps administrator wants to minimize compute costs. Which purchasing option should be used?

Accepted Answer

Spot Instances. Spot Instances are the correct choice because the batch job is fault-tolerant (can be interrupted and resumed) and runs for a fixed 2-hour window nightly. Spot Instances offer up to 90% cost savings compared to On-Demand, and with the ability to handle interruptions via checkpointing, they minimize compute costs without requiring a long-term commitment.

Answer

Reserved Instances

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On-Demand Instances

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Dedicated Instances

Question 7

A SysOps administrator wants to identify underutilized Amazon EC2 instances that could be downsized to reduce costs. The administrator needs a tool that provides recommendations based on historical utilization data. Which AWS service should the administrator use?

Accepted Answer

AWS Compute Optimizer. AWS Compute Optimizer is the correct service because it analyzes historical utilization metrics (CPU, memory, network, and storage) for EC2 instances and generates specific downsizing recommendations to reduce cost without sacrificing performance. It uses machine learning to identify underutilized resources and provides actionable guidance, making it the ideal tool for this use case.

Answer

AWS Trusted Advisor

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AWS Cost Explorer

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AWS Budgets

Question 8

A company runs an e-commerce application on Amazon EC2 instances behind an Auto Scaling group. The application has a predictable baseline load from 8 AM to 8 PM daily and low load overnight. The SysOps administrator wants to optimize costs while ensuring sufficient capacity for the baseline load. Which purchasing option and scaling strategy should the administrator use?

Accepted Answer

Use Reserved Instances for the predicted baseline and On-Demand for any unexpected spikes.. Reserved Instances provide a significant discount (up to 72%) over On-Demand for predictable, steady-state workloads like the 8 AM to 8 PM baseline. On-Demand instances then cover any unexpected spikes without requiring upfront commitment, ensuring cost optimization while maintaining capacity for the predictable load.

Answer

Use On-Demand instances for the baseline and Spot Instances for any additional capacity.

Answer

Use Dedicated Hosts for all instances to maximize cost savings.

Answer

Use Spot Instances for all instances to minimize costs.

Question 9

A SysOps administrator notices that an Amazon RDS DB instance is running at 10% CPU utilization consistently. The instance has 8 vCPUs and 32 GB RAM. The application's performance is adequate. Which action will reduce costs without affecting performance?

Accepted Answer

Change the DB instance to a smaller instance type.. The DB instance is over-provisioned for the current workload, as evidenced by the consistently low CPU utilization (10%) and adequate application performance. By changing to a smaller instance type, you reduce compute costs directly while maintaining sufficient capacity for the workload. This is the most straightforward cost optimization action when performance requirements are already met.

Answer

Enable Multi-AZ deployment for the DB instance.

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Change the storage type from gp2 to gp3.

Answer

Increase the provisioned IOPS.

Question 10

A company runs a stateless web application on Amazon EC2 instances behind an Application Load Balancer. The application usage is consistent throughout the day and is expected to grow steadily over the next year. The SysOps administrator wants to minimize compute costs while ensuring capacity is available. Which purchasing option should the administrator use for the EC2 instances?

Accepted Answer

Reserved Instances (Standard, 1-year or 3-year). The application has a steady, predictable usage pattern and is expected to grow steadily, making Reserved Instances (Standard) the most cost-effective option. By committing to a 1-year or 3-year term, the administrator can receive a significant discount (up to 72% compared to On-Demand) while ensuring capacity is always available. This aligns with the requirement to minimize compute costs without sacrificing availability for a stateless, load-balanced workload.

Answer

On-Demand Instances

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Spot Instances

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Dedicated Hosts

Question 11

A company runs a batch processing application on Amazon EC2 instances. The application runs for 3 hours every night and can tolerate interruptions. The SysOps administrator needs to minimize compute costs. Which purchasing option should the administrator use?

Accepted Answer

Spot Instances. Spot Instances are ideal for this workload because the application is fault-tolerant (can tolerate interruptions) and runs on a fixed schedule (3 hours nightly). Spot Instances offer significant cost savings (up to 90% compared to On-Demand) by using spare EC2 capacity, and the batch processing can be designed to resume from checkpoints if interrupted.

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On-Demand Instances

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Reserved Instances

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Dedicated Instances

Question 12

A company runs a web application on Amazon EC2 instances that run 24/7. The application has a predictable and steady load. The SysOps administrator wants to minimize compute costs while ensuring the required capacity is always available. Which purchasing option should be used?

Accepted Answer

Reserved Instances. Reserved Instances (RIs) are the correct choice because the workload runs 24/7 with a predictable and steady load. By committing to a 1- or 3-year term, the company can achieve a significant discount (up to 72%) compared to On-Demand pricing, while ensuring capacity is always available. This aligns with the goal of minimizing compute costs without sacrificing availability.

Answer

On-Demand Instances

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Spot Instances

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Dedicated Hosts

Question 13

A company stores application log files in an Amazon S3 bucket. The logs are accessed frequently for the first 30 days, then rarely accessed but must be retrievable within 12 hours. After 1 year, the logs must be archived for compliance with a retention period of 5 years, during which retrievals are expected to be extremely rare (one or two per year) and retrieval time of 12 hours is acceptable. The SysOps administrator wants to minimize storage costs. Which S3 lifecycle policy configuration should be used?

Accepted Answer

After 30 days, transition to S3 Glacier Flexible Retrieval; after 365 days, transition to S3 Glacier Deep Archive; delete after 5 years.. It uses S3 Glacier Flexible Retrieval for the first year after the initial 30 days, which meets the 12-hour retrieval requirement at lower cost than S3 Standard-IA, then transitions to S3 Glacier Deep Archive for the remaining 4 years to minimize storage costs for extremely rare retrievals. The lifecycle policy transitions objects after 30 days to S3 Glacier Flexible Retrieval (retrieval time minutes to 12 hours), then after 365 days to S3 Glacier Deep Archive (retrieval time 12 hours), and deletes after 5 years, aligning with the access patterns and compliance retention.

Answer

After 30 days, transition to S3 Standard-IA; after 365 days, transition to S3 Glacier Deep Archive; delete after 5 years.

Answer

After 30 days, transition to S3 Glacier Flexible Retrieval; delete after 5 years.

Answer

After 30 days, transition to S3 Glacier Deep Archive; delete after 5 years.

Question 14

A company runs a web application on Amazon EC2 instances in an Auto Scaling group. The application uses Amazon EBS volumes (gp2) for data storage. The SysOps administrator notices that the storage costs are high, and the application's IOPS requirements are consistently below 3000. The administrator wants to reduce storage costs without affecting performance. Which action should the administrator take?

Accepted Answer

Convert the EBS volumes from gp2 to gp3 volume type.. Gp3 volumes offer a baseline performance of 3000 IOPS and 125 MB/s throughput at a lower cost than gp2 volumes, making them ideal for workloads with IOPS requirements consistently below 3000. By converting from gp2 to gp3, the administrator can reduce storage costs without any performance impact, as gp3 provides the same or better baseline performance at a lower price per GB.

Answer

Modify the EBS volumes to use Provisioned IOPS (io1) volumes and set IOPS to 2000.

Answer

Implement an Amazon EBS snapshot lifecycle policy to delete old snapshots and reduce storage costs.

Answer

Enable EBS optimization on the EC2 instances to improve throughput and reduce costs.

Question 15

A company runs a web application on a fleet of Amazon EC2 instances that operate 24/7 with a steady and predictable load. The SysOps administrator wants to minimize compute costs while ensuring the required capacity is always available. Which EC2 purchasing option should the administrator use?

Accepted Answer

Reserved Instances. Reserved Instances (RIs) are the correct choice because the workload runs 24/7 with steady, predictable load. RIs provide a significant discount (up to 72%) over On-Demand pricing in exchange for a one- or three-year commitment, ensuring cost minimization while guaranteeing capacity availability in the specified Availability Zone.

Answer

Spot Instances

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On-Demand Instances

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Dedicated Hosts