Cost optimization strategies in GCP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main goal of cost optimization in cloud computing?

To reduce cloud spending while maintaining performance and reliability.

beginner

How can committed use contracts help reduce costs in GCP?

By committing to use a certain amount of resources for 1 or 3 years, you get a significant discount compared to pay-as-you-go pricing.

intermediate

What is the benefit of using Preemptible VMs in Google Cloud?

They offer much lower prices but can be stopped by Google at any time, suitable for short, fault-tolerant workloads.

beginner

Why is monitoring and setting budgets important for cost optimization?

It helps detect unexpected spending early and keeps cloud costs under control by alerting you before costs get too high.

intermediate

How does rightsizing resources help optimize costs?

By adjusting resource sizes to match actual needs, you avoid paying for unused capacity.

Which GCP feature offers discounts in exchange for a long-term commitment?

A On-demand pricing

B Preemptible VMs

C Sustained use discounts

D Committed use contracts

Committed use contracts require you to commit to resource usage for 1 or 3 years to get discounts.

What is a key risk when using Preemptible VMs?

A They can be stopped at any time by Google

B They cost more than regular VMs

C They have no network access

D They cannot run containers

Preemptible VMs can be terminated by Google at any time, so they are best for fault-tolerant workloads.

Which practice helps avoid paying for unused cloud capacity?

A Rightsizing resources

B Increasing VM size

C Using more storage than needed

D Disabling monitoring

Rightsizing means adjusting resources to fit actual needs, avoiding waste.

Why should you set budgets and alerts in GCP?

A To disable billing

B To increase spending automatically

C To get notified before costs exceed limits

D To delete resources automatically

Budgets and alerts help you monitor and control cloud spending.

What is a sustained use discount in GCP?

A A discount for prepaying for resources

B A discount for running resources for a large portion of the month

C A discount for using only small VMs

D A discount for using multiple regions

Sustained use discounts automatically lower prices when you use resources continuously during the month.

Explain three strategies to optimize costs in Google Cloud Platform.

Think about discounts, cheaper VM options, adjusting resource sizes, and tracking spending.

Describe how monitoring and budgeting help control cloud costs.

Consider how knowing your spending early can prevent surprises.

Practice

1. Which of the following is a basic way to reduce costs in Google Cloud Platform (GCP)?

easy

A. Use the most powerful machines regardless of need

B. Increase the number of virtual machines

C. Use smaller or cheaper machine types

D. Keep all resources running 24/7

Solution

1. Step 1: Understand cost drivers in GCP

   Machine types with more CPU and memory cost more money.

2. Step 2: Choose cost-saving options

   Using smaller or cheaper machine types reduces the hourly cost.

3. Final Answer:

   Use smaller or cheaper machine types -> Option C

4. Quick Check:

   Smaller machines cost less [OK]

Hint: Pick smaller machines to save money quickly [OK]

Common Mistakes:

• Thinking more machines always save money
• Believing running all resources nonstop is cheaper
• Choosing the most powerful machines by default

2. Which of the following is the correct way to specify a preemptible VM in a GCP instance creation command?

easy

A. gcloud compute instances create my-vm --preemptible

B. gcloud compute instances create my-vm --no-preemptible

C. gcloud compute instances create my-vm --machine-type=preemptible

D. gcloud compute instances create my-vm --enable-preemptible=false

Solution

1. Step 1: Review gcloud syntax for preemptible VMs

   The flag to create a preemptible VM is --preemptible.

2. Step 2: Identify the correct command

   gcloud compute instances create my-vm --preemptible uses --preemptible correctly to enable preemptible VM.

3. Final Answer:

   gcloud compute instances create my-vm --preemptible -> Option A

4. Quick Check:

   Use --preemptible flag to create preemptible VM [OK]

Hint: Look for --preemptible flag to enable preemptible VMs [OK]

Common Mistakes:

• Using --no-preemptible which disables preemptible
• Confusing machine-type with preemptible flag
• Using incorrect flag names

3. Consider this Python snippet using GCP SDK to list VM instances and filter by machine type for cost optimization:

instances = [
  {"name": "vm1", "machine_type": "n1-standard-1"},
  {"name": "vm2", "machine_type": "n1-highmem-4"},
  {"name": "vm3", "machine_type": "n1-standard-1"}
]
cheap_vms = [vm["name"] for vm in instances if vm["machine_type"] == "n1-standard-1"]
print(cheap_vms)

What is the output?

medium

A. ['vm2']

B. ['vm1', 'vm3']

C. ['vm1', 'vm2', 'vm3']

D. []

Solution

1. Step 1: Understand the list comprehension filter

   The code selects VMs where machine_type equals 'n1-standard-1'.

2. Step 2: Identify matching VMs

   vm1 and vm3 have 'n1-standard-1', vm2 does not.

3. Final Answer:

   ['vm1', 'vm3'] -> Option B

4. Quick Check:

   Filter by machine_type 'n1-standard-1' gives vm1 and vm3 [OK]

Hint: Filter list by machine_type to find cheaper VMs [OK]

Common Mistakes:

• Including vm2 which has a different machine type
• Returning empty list by mistake
• Confusing keys in dictionary

4. You wrote this command to create a preemptible VM but it keeps creating normal VMs:

gcloud compute instances create cheap-vm --machine-type=n1-standard-1 --enable-preemptible=false

What is the error and how to fix it?

medium

A. The VM name is invalid; rename it

B. The machine type is wrong; use a cheaper type

C. The command is missing zone specification

D. The flag disables preemptible; use --preemptible instead

Solution

1. Step 1: Analyze the preemptible flag usage

   The flag --enable-preemptible=false disables preemptible VMs.

2. Step 2: Correct the flag to enable preemptible

   Use --preemptible without false to create preemptible VM.

3. Final Answer:

   The flag disables preemptible; use --preemptible instead -> Option D

4. Quick Check:

   Use --preemptible to enable preemptible VMs [OK]

Hint: Use --preemptible flag alone to enable preemptible VMs [OK]

Common Mistakes:

• Using --enable-preemptible=false disables preemptible
• Changing machine type instead of flag
• Ignoring flag syntax errors

5. A company wants to optimize costs by automatically stopping VMs when not in use during nights and weekends. Which GCP service or strategy best supports this goal?

hard

A. Use Cloud Scheduler to trigger Cloud Functions that stop/start VMs on schedule

B. Manually stop VMs every night using the console

C. Use preemptible VMs only without scheduling

D. Increase VM size to reduce runtime

Solution

1. Step 1: Identify automation options for VM management

   Cloud Scheduler can run tasks on a schedule, and Cloud Functions can execute commands like stopping VMs.

2. Step 2: Match automation to cost optimization goal

   Automating stop/start reduces costs by not running VMs when unused.

3. Final Answer:

   Use Cloud Scheduler to trigger Cloud Functions that stop/start VMs on schedule -> Option A

4. Quick Check:

   Automate VM stop/start with Cloud Scheduler and Functions [OK]

Hint: Automate VM stop/start with Cloud Scheduler and Functions [OK]

Common Mistakes:

• Relying on manual stopping which is error-prone
• Using preemptible VMs without scheduling
• Increasing VM size which raises costs