DCA Financial Management & Budgeting 5

Question 1

Which Docker Swarm placement constraint would you use to schedule cost-intensive GPU workloads only on GPU-equipped nodes?

Accepted Answer

--constraint 'node.labels.gpu==true'

Answer

Custom node labels like gpu=true combined with placement constraints route containers only to nodes with that capability.

Question 2

A container's --cpu-quota is set to 50000 with the default --cpu-period of 100000. What percentage of a single CPU can this container use?

Accepted Answer

50%

Answer

cpu-quota divided by cpu-period equals 50000 / 100000 = 0.5, so the container can consume at most 50% of one CPU per period.

Question 3

Which open-source tool stack is commonly integrated with Docker to provide container-level resource metrics for cost attribution and chargeback?

Accepted Answer

cAdvisor with Prometheus and Grafana

Answer

cAdvisor exposes per-container resource metrics that Prometheus scrapes and Grafana visualizes, enabling department-level cost reporting.

Question 4

What is the effect of setting --blkio-weight=100 on a container compared to the default weight of 500?

Accepted Answer

The container gets proportionally less block I/O bandwidth than default-weight containers

Answer

blkio-weight is a relative value; 100 vs 500 means the container gets roughly 1/5 of the I/O share compared to a default-weighted container.

Question 5

An engineering team wants to reduce Docker image pull times and egress costs in a multi-region deployment. Which architecture best achieves this?

Accepted Answer

Deploy a regional Docker registry mirror or pull-through cache close to each cluster

Answer

A regional registry mirror stores images locally, cutting cross-region egress fees and reducing pull latency.

DCA - Docker Certified Associate Exam Practice Test