Google ACE Planning and configuring a cloud solution Practice Test 2 — 15 Questions

Question 1

A startup builds a serverless REST API using Cloud Functions (2nd gen). Each function invocation runs for 200ms on average, processes 5 million requests per day, and uses 256 MB memory. Approximately how should they estimate monthly Cloud Functions costs?

Accepted Answer

Estimate based on invocation count, compute time (memory × duration), and networking costs beyond the free tier. Option B is correct because Cloud Functions (2nd gen) pricing is based on three components: invocation count, compute time (measured in GB-seconds, which is memory multiplied by duration), and networking egress beyond the free tier. With 5 million requests per day at 200ms each and 256 MB memory, the monthly compute time is approximately 5,000,000 × 0.2 seconds × (256/1024) GB = 250,000 GB-seconds per day, or 7.5 million GB-seconds per month, which far exceeds the free tier of 400,000 GB-seconds per month, so costs will accrue. Additionally, the 150 million invocations per month exceed the free tier of 2 million invocations, and egress traffic will also incur charges beyond the 1 GB free tier.

Answer

Approximately $0 — all invocations fall within the free tier

Answer

Approximately the same as a continuously-running e2-medium VM — Cloud Functions and VMs are priced equivalently

Answer

Fixed monthly rate based on the number of deployed functions, not invocation count

Question 2

A startup runs its application entirely on Cloud Run. They want to use a custom domain (api.mycompany.com) instead of the default Cloud Run URL. Which GCP feature maps a custom domain to a Cloud Run service?

Accepted Answer

Cloud Run Domain Mappings or a Global Load Balancer with a Serverless NEG. Option B is correct because Cloud Run Domain Mappings provide a native, managed way to map a custom domain to a Cloud Run service without additional infrastructure. Alternatively, a Global Load Balancer with a Serverless NEG (Network Endpoint Group) can also route traffic from a custom domain to Cloud Run, offering advanced features like SSL termination and traffic splitting. Both approaches are officially supported by Google Cloud for custom domain mapping.

Answer

Cloud DNS — create a CNAME record pointing to the Cloud Run URL

Answer

Cloud Endpoints with an API gateway configuration

Answer

Firebase Hosting rewrites to Cloud Run

Question 3

A SaaS company serves 200 enterprise customers, each requiring complete data isolation in separate databases. The company needs to provision a new customer database within minutes and manage 200 databases with minimal overhead. Which GCP approach scales most efficiently?

Accepted Answer

A single Cloud SQL instance with a separate schema (database) per customer, provisioned via API automation. Option B is correct because it uses a single Cloud SQL instance with separate schemas (databases) per customer, which allows you to achieve complete data isolation while minimizing overhead. Provisioning a new schema via API automation takes seconds, and managing 200 schemas on one instance is far more efficient than managing 200 separate instances. This approach scales efficiently because Cloud SQL supports up to 10,000 databases per instance, and you can leverage connection pooling and shared resources without sacrificing isolation.

Answer

200 separate Cloud SQL instances, one per customer

Answer

Storing all customer data in a single shared database with customer_id as a discriminator column

Answer

Using BigQuery with a separate dataset per customer

Question 4

A team builds a document processing pipeline: files are uploaded to Cloud Storage, then analyzed by Cloud Vision AI, results stored in Firestore, and a confirmation email sent. Each step depends on the previous. Which GCP service orchestrates these sequential, dependent steps reliably?

Accepted Answer

Cloud Workflows. Cloud Workflows is designed to orchestrate sequential, dependent steps with built-in retry, error handling, and state management. It directly models the pipeline as a series of steps where each step's output feeds the next, without requiring manual chaining or intermediate messaging infrastructure.

Answer

Cloud Pub/Sub with a subscription per step

Answer

Cloud Tasks with per-step queues

Answer

Cloud Functions chained via HTTP calls

Question 5

An application architect is comparing Cloud SQL (PostgreSQL) and Cloud Spanner for a new global e-commerce platform. The platform must serve customers on three continents with <50ms latency for reads and strong consistency for inventory updates. Which service best fits?

Accepted Answer

Cloud Spanner multi-region configuration. Cloud Spanner multi-region configuration is the correct choice because it provides strong global consistency with <50ms read latency across continents, which is essential for an e-commerce platform requiring real-time inventory updates. Spanner uses TrueTime and Paxos-based replication to ensure ACID transactions globally, meeting both the latency and consistency requirements simultaneously.

Answer

Cloud SQL with one primary instance and cross-region read replicas

Answer

Cloud Firestore in multi-region mode

Answer

Cloud SQL with Cloud Memorystore caching layer for reads

Question 6

A payment service publishes an event to a message queue every time a transaction completes. Multiple downstream services (inventory, analytics, email) must each process every event independently. Which messaging pattern and GCP service best supports this?

Accepted Answer

Cloud Pub/Sub with one subscription per downstream service on a shared topic. Cloud Pub/Sub with a single topic and one subscription per downstream service is the correct pattern because it implements a fan-out messaging model where each subscriber receives an independent copy of every published message. This ensures that inventory, analytics, and email services each process every transaction event without interference, while Pub/Sub handles at-least-once delivery and automatic scaling.

Answer

Cloud Tasks with one queue per downstream service

Answer

Cloud Storage event notifications with three separate buckets

Answer

Directly calling each downstream service's API synchronously from the payment service

Question 7

A team must choose between Cloud Pub/Sub and Cloud Tasks for a use case where jobs must be delivered to a single HTTP endpoint, each job executed at most once, with rate limiting to 10 requests per second, and with retry on failure. Which service is the better fit and why?

Accepted Answer

Cloud Tasks — it provides rate limiting, at-most-once delivery via deduplication, and targeted HTTP dispatch. Cloud Tasks is the better fit because it is designed for targeted HTTP dispatch to a single endpoint, supports rate limiting (max bursts per second), and provides at-most-once delivery via task deduplication (based on a unique task ID). Cloud Pub/Sub push subscriptions do not offer built-in rate limiting and guarantee at-least-once delivery, not at-most-once.

Answer

Cloud Pub/Sub — it supports rate-limited push subscriptions and at-most-once delivery

Answer

Cloud Pub/Sub with a Dataflow consumer applying rate limiting

Answer

Both are equivalent for this use case — choose based on cost

Question 8

An engineering team is deciding between App Engine Standard and App Engine Flexible for a Python API. The API has unpredictable traffic, must scale to zero when idle, runs standard Python code with no custom system packages, and requires < 1 second startup time. Which environment is most suitable?

Accepted Answer

App Engine Standard — it scales to zero, starts in sub-second, and supports standard Python runtimes. App Engine Standard is the correct choice because it automatically scales to zero instances during idle periods, starts new instances in under a second, and supports standard Python runtimes without custom system packages. The requirement for sub-second startup time and scaling to zero aligns perfectly with Standard's sandboxed, pre-loaded runtime environment, whereas Flexible environment has slower startup times due to VM provisioning and cannot scale to zero.

Answer

App Engine Flexible — it supports Python with custom packages

Answer

Both are equivalent — the difference is only in supported languages

Answer

Neither — use Cloud Run instead for Python APIs

Question 9

A team is designing a system where two GCP projects — a shared services project and an application project — need their VMs to communicate using private IPs. Both projects are in the same organization. Which networking option best enables this with centralized network management?

Accepted Answer

Shared VPC (XPN) with the shared services project as the host. Shared VPC (XPN) allows an organization to centrally manage networking across multiple projects from a single host project, enabling VMs in the shared services project and the application project to communicate via private IPs without needing separate peering or VPN configurations. This is the best option because it provides centralized network administration and policy enforcement, which aligns with the requirement for centralized network management.

Answer

VPC Peering between the two projects' VPCs

Answer

Cloud VPN between the two projects' default VPCs

Answer

Using external IPs with TLS — private IP communication isn't necessary between GCP projects

Question 10

A data warehouse team queries a 10 TB BigQuery table containing billions of events with a date column. Most queries filter by a date range (e.g., last 30 days). Without any partitioning, queries scan the full 10 TB every time. Which BigQuery feature eliminates unnecessary data scanning for date-range queries?

Accepted Answer

Date/timestamp partitioned table on the date column. Partitioning a BigQuery table by the date column allows the query engine to prune entire partitions that fall outside the specified date range, so only the relevant partitions (e.g., last 30 days) are scanned instead of the full 10 TB. This directly reduces data scanned and cost, making option C the correct choice for eliminating unnecessary scanning in date-range queries.

Answer

BigQuery table clustering on the date column

Answer

Creating a materialized view for the last 30 days

Answer

Increasing BigQuery slot reservations for faster full-table scans

Question 11

A global web application serves static assets (images, JavaScript, CSS) from a Cloud Storage bucket via an HTTPS load balancer. Users in Asia report slow load times compared to users in the US where the bucket resides. What is the most effective solution?

Accepted Answer

Enable Cloud CDN on the load balancer backend pointing to the Cloud Storage bucket. Option B is correct because enabling Cloud CDN on the load balancer backend that points to the Cloud Storage bucket caches static assets at Google's globally distributed edge caches. This reduces latency for Asian users by serving content from a nearby point of presence (PoP) rather than from the origin bucket in the US, without requiring any bucket relocation or replication.

Answer

Move the Cloud Storage bucket to a multi-region bucket in Asia

Answer

Replicate the Cloud Storage bucket to multiple regions using storage transfer

Answer

Use Cloud Interconnect to provide dedicated bandwidth to Asian users

Question 12

A team deploys an application on GKE and needs it to be accessible at https://api.company.com with automatic TLS certificate provisioning. They use a Global external Application Load Balancer. What handles the TLS certificate?

Accepted Answer

A Google-managed SSL certificate attached to the load balancer's HTTPS target proxy. A Global external Application Load Balancer uses an HTTPS target proxy to terminate TLS. To automatically provision and renew TLS certificates for a custom domain, you attach a Google-managed SSL certificate to that target proxy. Google manages the entire lifecycle, including domain verification via Cloud DNS, so no manual certificate generation or third-party tools are needed.

Answer

The GKE cluster automatically generates a self-signed TLS certificate for the domain

Answer

Cloud DNS automatically provisions a TLS certificate when a domain is added

Answer

cert-manager in GKE automatically obtains Let's Encrypt certificates for the Ingress

Question 13

Microservices in a GKE cluster need to discover each other by name without using public DNS. Service A calls Service B at `http://service-b.production.svc.cluster.local`. Which GCP/Kubernetes feature provides this internal DNS resolution?

Accepted Answer

Kubernetes cluster DNS (CoreDNS) resolving Service names within the cluster. Kubernetes cluster DNS, typically implemented by CoreDNS, is the built-in mechanism that resolves Service names like `service-b.production.svc.cluster.local` to the corresponding ClusterIP. This allows Pods to discover each other by name without relying on external or public DNS. CoreDNS runs as a Deployment in the kube-system namespace and automatically creates DNS records for every Service based on its name and namespace.

Answer

Cloud DNS private zone configured for the cluster's namespace

Answer

Anthos Service Mesh — required for service-to-service DNS

Answer

A custom /etc/hosts entry on each Pod

Question 14

A startup's application uses both GCP services and an existing on-premises Kubernetes cluster. They want a single control plane to manage Kubernetes clusters across both environments with consistent policy enforcement. Which Google service provides this?

Accepted Answer

Anthos (Google Distributed Cloud) for hybrid multi-cluster management. Anthos (Google Distributed Cloud) is the correct answer because it provides a unified control plane for managing Kubernetes clusters across on-premises and GCP environments, enabling consistent policy enforcement, configuration, and observability. Anthos uses GKE on-prem and GKE in the cloud, with a centralized Anthos Config Management and Service Mesh for policy and security consistency, directly addressing the hybrid multi-cluster management requirement.

Answer

GKE Hub (Fleet management)

Answer

Cloud Interconnect — connects on-premises clusters to GCP so they share a control plane

Answer

Cloud Composer — a managed Kubernetes workflow across environments

Question 15

A team is selecting the right Compute Engine machine family for a machine learning training workload that is GPU-bound. The workload runs for 6 hours at a time and tolerates interruption. Which combination maximizes GPU access at lowest cost?

Accepted Answer

A2 or A3 (accelerator-optimized) Spot VM with NVIDIA GPU. Option B is correct because A2 and A3 Spot VMs are purpose-built for GPU-bound ML training workloads, offering direct access to NVIDIA GPUs (e.g., A100, H100) at the lowest cost due to Spot pricing (60-91% discount). The workload's 6-hour duration and interruption tolerance make Spot VMs ideal, as they can be preempted but provide maximum GPU utilization for the price.

Answer

N2-standard machine with a custom GPU attached as a standard on-demand VM

Answer

E2-highcpu Spot VM — more vCPUs provide equivalent GPU-like parallelism

Answer

C3 (compute-optimized) on-demand VM — best for numerically intensive workloads