Function Compute supports the subscription billing method. You can purchase a CU subscription with a specified lifecycle. Within the lifecycle, the resources consumed by function execution are deducted from your CU subscription each second. If you purchase a CU subscription, you can obtain the same resources at a lower cost.

What is a CU subscription?

Note The subscription billing method is supported only for function instance resources. For more information, see Billable items.

A CU subscription, during its lifecycle, can be used to deduct the resources that function instances use for function execution each second.

  • Unit: CU, one CU covers 1 GB of resource usage per second.
  • Resource deduction type: constant. Unless the CU subscription is upgraded, its resources per second for resource deduction remain constant regardless of consumption. In essence, a CU subscription is similar to a bandwidth plan, not to a data transfer plan.
  • Resources to be deducted: Resources used by both reserved and pay-as-you-go instances can be deducted from a CU subscription.


Unit Unit price Description
1 CU-month USD 12.16 30 × 24 × 60 × 60 × CNY 0.00003167 (assuming 30 days in a month)

Purchase limits

  • A maximum of 1,000 CU can be purchased in a single order.
  • All orders in a region can have a maximum of 1,000 CU in total. If you want to increase this limit, submit a ticket.
    Note You can increase the maximum number of CUs in a region, but not that of your per-order CUs. To purchase more CUs, you can place multiple orders.
  • Your CU subscription can be used only in the region that is specified when you purchase the CU subscription.

Purchase a CU subscription

The following operations can be performed for Function Compute CU subscriptions:
  • New purchase: You can purchase a CU subscription in a region and specify the subscription lifecycle. For more information, see Manage new purchases.
  • Upgrade: You can upgrade the CU subscription for a specified instance so that more resources can be covered in a unit of time. For more information, see Manage upgrades.
  • Renewal: You can extend the lifecycle of a specified CU subscription. For more information, see Manage renewals.
    • Manual renewal: You can manually renew a CU subscription.
    • Auto-renewal: You can enable auto-renewal to automatically trigger a renewal request before the lifecycle of the CU subscription ends.
  • An order is generated for each new purchase, renewal, and upgrade. Each order has a globally unique ID.
  • A unique instance ID is generated for each new purchase. This ID is used throughout the order lifecycle for all subsequent operations, such as renewals and upgrades.

Billing example

In this example, the total number of CUs for all function instances on the account and the amount deducted from the resource quota are calculated for each second.

For example, assume that you purchased a voucher for 30 CU. In this case, 30 CU can be deducted at the subscription rate each second.exampleresource
  • In second 1, instance 1 consumed 20 CU-second (40 CU × 0.5 seconds).
  • In second 2, instance 1 and instance 2 consume a total of 50 CU-second (40 CU × 0.75 seconds + 20 CU × 1 second).
  • In second 3, instance 2 and instance 3 consumed 30 CU-second (20CU × 1 second + 10 CU × 1 second).
  • In second 4, instance 2 consumed 20 CU-second (20 CU × 1 second).
The cost details are shown in the following table.
Time window Actual resource consumption (CU-second) All subscription resources (CU-second) Additionally billed resources (CU-second)
Second 1 20 30 0
Second 2 50 30 20
Second 3 30 30 0
Second 4 20 30 0