This page describes how committed use discounts work with Cloud SQL.
What are Cloud SQL committed use discounts?
Committed use discounts (CUDs) for Cloud SQL provide deeply discounted prices in exchange for committing to continuously use database instances in a particular region for a one- or three-year term.
Cloud SQL committed use discounts are ideal for workloads with predictable resource needs. You commit to a consistent amount of usage, measured in $/hour of equivalent on-demand spend, for a one- or three-year term. In exchange, you receive a discounted rate on the applicable usage your commitment covers. You can purchase committed use discounts from any Cloud Billing account, and the discount applies to any eligible usage in projects paid for by that Cloud Billing account. Any overage is charged at the on-demand rate. When you purchase a Cloud SQL committed use discount, you pay the same commitment fee for the entirety of the commitment term, even if the price of applicable usage changes. You still receive the same discount percentage on applicable usage in the event of a price change. The commitment fee is billed monthly.
For more information about the bill, see Analyze the effectiveness of your spend-based committed use discounts.
What usage do Cloud SQL committed use discounts apply to?
Committed use discounts automatically apply to aggregate Cloud SQL instance usage in a region, giving you low, predictable costs, without the need to make any manual changes or updates yourself. This flexibility saves you time and helps you to save more by achieving high utilization rates across your commitments.
Cloud SQL committed use discounts apply to all Cloud SQL database instance CPU and memory usage in the region in which you have committed, except shared CPU machine types (such as db-f1-micro and db-g1-small). Cloud SQL committed use discounts apply to usage from all supported databases (for example, MySQL, PostgreSQL, and SQL Server). Cloud SQL committed use discounts do not apply to storage, backups, IP Addresses, network egress, or licensing.
Cloud SQL committed use discounts give you a 25% discount off on-demand pricing for a one-year commitment and a 52% discount off on-demand pricing for a three-year commitment. These discount percentages are the same in every region.
See committed use discount pricing for pricing details.
Purchasing Cloud SQL committed use discounts
You can purchase a Cloud SQL committed use discount in the Google Cloud Console billing page. Select the Commitments tab, then select the PURCHASE action at the top. After purchasing a committed use discount, the commitment is effective starting within the next hour. The discounts are automatically applied to eligible usage in the region you specified.
Before you purchase a commitment, read the Service Specific Terms regarding Committed Units.
To learn more, including how to purchase spend-based commitments, see Committed use discounts.
Example use case
Key points to keep in mind:
- Cloud SQL committed use discounts only apply to vCPUs and memory.
- Cloud SQL committed use discounts do not apply to storage, backups, IP Addresses, network egress, or licensing.
- Cloud SQL committed use discounts apply to all instances in a given region.
- Cloud SQL committed use discounts are measured in dollars per hourly on-demand commitment.
How to calculate hourly on-demand commitment
You calculate the baseline per hour cost of vCPUs + Memory across all instances in the region you want to benefit from a committed use discount. Any usage above that limit will be charged at the regular on-demand price.
- Assume you are running 100 instances in each of two different regions. The instances are using 2 high availability (HA) vCPUs with 7.5GB HA RAM, and are located in regions us-central1 (Iowa) and asia-southeast1 (Singapore), and you're interested in buying a 1-year committed use discount.
From the pricing table, we can calculate the total hourly commitment cost per region:
- 100 * 2x HA vCPU * $0.0826 per vCPU/hour = ~$16.50 / hour
- 100 * 7.5GB HA RAM * $0.0140 per GB/hour = ~$10.00 / hour
- For a total of $26.50 per hour in committed use hourly pricing
- 100 * 2x HA vCPU * $0.1156 per vCPU/hour = ~$21.00 / hour
- 100 * 7.5GB HA RAM * $0.0735 per GB/hour = ~$14.00 / hour
- For a total of $35.00 per hour in committed use hourly pricing
Calculating the monthly cost (720 hours in a month):
- On-demand pricing = ($26.50/hour * 720 hours) = $19,080 / month
- After 25% 1-year CUD discount = $14,310 / month
- Totals a savings of $4,770 / month
- On-demand pricing = ($35/hour * 720 hours) = $25,200 / month
- After 25% 1-year CUD discount = $18,900 / month
- Totals a savings of $6,300 / month
Once you make the commitment, you're charged that amount even if you decide to stop or scale down the actual number of vCPUs or RAM during the month.
When making the decision on whether to purchase committed use discounts, keep in mind the following considerations:
- Regions: CUDs are purchased by region. If you are running in multiple regions, calculate and purchase CUDs in each region separately.
- Projects: Determine the consistent baseline vCPU/RAM usage per project. Consider that production loads usually run 100% of the time, while development or staging environments may be run more intermittently.
- Instances: Cloud SQL instances are usually run 24/7, so it's common to buy CUDs for 100% consumption. If you have instances that are run only for bursts or shorter durations, exclude them from your calculations, and pay on-demand rates for those instances.
- Machine types: Committed use discounts are not tied to any machine type, just the total of vCPUs and amount of memory used in the region.