DCA Financial Management & Budgeting 2

Question 1

A DevOps team wants to prevent a single container from consuming all available memory on a host. Which Docker run flag enforces a hard memory limit?

Accepted Answer

--memory

Answer

The --memory flag sets a hard limit on the maximum RAM a container can use.

Question 2

Your organization runs Docker containers on AWS EC2 instances. Which approach best reduces infrastructure costs when workloads are unpredictable?

Accepted Answer

Use Spot Instances with Docker Swarm for fault-tolerant services

Answer

Spot Instances are significantly cheaper and Docker Swarm can reschedule containers when spots are reclaimed.

Question 3

Which Docker command shows real-time resource consumption (CPU, memory, I/O) for all running containers to help identify cost-driving processes?

Accepted Answer

docker stats

Answer

docker stats streams live resource usage metrics for all running containers by default.

Question 4

A container is configured with --memory=512m --memory-swap=512m. What does this configuration imply about swap usage?

Accepted Answer

The container cannot use any swap memory

Answer

When --memory-swap equals --memory, the container is not allowed to use any swap space.

Question 5

Which Docker resource constraint flag limits the proportion of CPU cycles a container can use relative to other containers?

Accepted Answer

--cpu-shares

Answer

--cpu-shares sets a relative weight for CPU scheduling when multiple containers compete for CPU time.

DCA - Docker Certified Associate Exam Practice Test