mediumMultiple Select
PDE Practice Question: Designing a streaming Dataflow pipeline that…
You are designing a streaming Dataflow pipeline that processes high-throughput data. Which two features can help minimize cost? (Choose TWO.)
⚠ Common exam trap
Google Cloud often tests the misconception that preemptible VMs are always cost-effective for streaming workloads, but the trap here is that preemptible VMs are unsuitable for stateful streaming pipelines due to frequent preemption causing data reprocessing and instability.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Enable autoscaling based on CPU utilization
Enabling autoscaling based on CPU utilization allows the Dataflow pipeline to dynamically adjust the number of worker instances in response to the actual processing load. This prevents over-provisioning during low-throughput periods, directly reducing compute cost while maintaining performance during spikes.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Enable autoscaling based on CPU utilization
Why this is correct
Autoscaling adjusts the number of workers to meet demand, avoiding over-provisioning and reducing cost.
- ✗
Use batch loads to BigQuery for streaming inserts
Why it's wrong here
Batch loads are not appropriate for streaming; they add latency and require multiple writes.
- ✓
Enable Streaming Engine to decouple compute and storage
Why this is correct
Streaming Engine reduces cost by allowing compute and state storage to scale independently, reducing idle resources.
- ✗
Use preemptible VMs for all workers
Why it's wrong here
Preemptible VMs are not recommended for streaming pipelines because they can be terminated at any time, causing data loss.
- ✗
Use a global window and batch output to BigQuery every hour
Why it's wrong here
Global windows are not suitable for streaming and may incur high costs due to long-running state.
Go deeper
Related to this question
About these practice questions
This PDE question is part of Courseiva's 747-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This PDE practice question is part of Courseiva's free Google Cloud certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PDE exam.