Compare Cloud Run functions

This guide compares the latest and original Google Cloud choices for deploying functions. This page helps those who previously created functions with the Cloud Functions API and are transitioning to the Cloud Run Admin API. This page describes key differences in several areas, such as concepts, configuration, deployment, and triggers and retries.

Comparison

There are two versions of Cloud Run functions:

  • Cloud Run functions, is the latest version of functions, deployed as a service on Cloud Run. They can be created in one of the following ways:

    • Cloud Run Admin API (Recommended): Functions created with this API (for example, by using Google Cloud console, gcloud run, the REST API, or Terraform) can be managed exclusively using the Cloud Run Admin API.
    • Cloud Functions v2 API: Functions created with this API (for example, by using gcloud functions, the REST API, or Terraform) can be managed with the Cloud Run Admin API as well as the Cloud Functions v2 API. When using this API, you specify the trigger when deploying your function. Learn how to detach a v2 API function so that it can be managed exclusively using the Cloud Run Admin API.

  • Cloud Run functions (1st gen), formerly known as Cloud Functions (1st gen), is the original version of functions with limited event triggers, runtimes, and configurability. Learn how to upgrade your 1st gen functions to Cloud Run.

By deploying functions directly onto Cloud Run, your functions are automatically built as containers and deployed as a Cloud Run service.

Concepts

The following table summarizes the conceptual differences for functions.

Cloud Run functions Cloud Run functions (1st gen)
Former product name Cloud Functions (2nd gen) Cloud Functions (1st gen)
Resource model A function is a Cloud Run service that is deployed from source code A function is deployed from source code
Types of functions terminology
  • HTTP functions
  • CloudEvents functions, also referred to as event-driven functions, are supported in all language runtimes.
  • HTTP functions
  • Only Ruby, .NET, and PHP runtimes support CloudEvents. For Node.js, Go, Python, and Java, create event-driven functions using Background functions.
Assigned HTTPS URL run.app

Functions created with the Cloud Functions v2 API also have a cloudfunctions.net endpoint.		 cloudfunctions.net
Image registry Artifact Registry only Artifact Registry or Container Registry (deprecated)
IAM roles for deployment
Internal infrastructure Cloud Run Google internal
Pricing model Cloud Run pricing Cloud Run functions (1st gen) pricing

Configuration

Cloud Run builds functions into containers and deploys them as services. When you deploy a function to Cloud Run, you have complete access and control over the function's behavior. For example, you can enable Direct VPC, configure GPUs, use volume mounts, and more.

The following table summarizes the configuration differences for functions:

Cloud Run functions Cloud Run functions (1st gen)
Request timeout
  • Up to 60 minutes for HTTP-triggered functions
  • Up to 9 minutes for event-driven functions created with the Cloud Functions v2 API
  • Up to 9 minutes
Instance size Up to 16 GiB RAM with 4 vCPU Up to 8 GB RAM with 2 vCPU
Concurrency Up to 1000 concurrent requests per function instance 1 concurrent request per function instance
Traffic splitting Supported Not supported

Deployment

Since August 2024, you can use Cloud Run to deploy and manage functions created with the Cloud Functions v2 API. As a result of this change:

  • Function metadata such as runtime ID and build configurations are stored in the Cloud Run service definition.
  • You can safely edit your function using the Cloud Run Admin API.
  • You can rely on the Cloud Run service definition as the source of truth for your function.

However, note that functions created with the Cloud Run Admin API cannot be modified with the Cloud Functions API.

The following table summarizes the differences in how you create, deploy, edit, and manage functions:

Cloud Run functions Cloud Run functions (1st gen)
Google Cloud console Cloud Run Cloud Run functions (1st gen)
Cloud SDK
REST API
  • run.googleapis.com (v1 and v2) for functions created with the Cloud Run Admin API or the Cloud Functions API.
Terraform

Deploy functions created with the Cloud Functions v2 API

As described previously, you can use Cloud Run tools to deploy and manage functions created with the Cloud Functions v2 API. If you need to deploy your function using the Cloud Functions v2 API (for example, for backward compatibility), you can do so as follows:

  1. Make sure you have the Cloud Functions Developer IAM role or a role that includes the same permissions. See also Additional configuration for deployment.

  2. Use the gcloud functions deploy command to deploy a function:

    gcloud functions deploy YOUR_FUNCTION_NAME \
   --region=YOUR_REGION \
   --runtime=YOUR_RUNTIME \
   --source=YOUR_SOURCE_LOCATION \
   --entry-point=YOUR_CODE_ENTRYPOINT \
   TRIGGER_FLAGS...

    Replace the following:

    • YOUR_FUNCTION_NAME: the name of the function you want to deploy to. The function name must start with a letter followed by up to 62 letters, numbers, hyphens, or underscores, and must end with a letter or a number. The name of the Cloud Run service that is created for your function will replace underscores with hyphens and uppercase letters will be converted to lowercase. For example, Function_1 will be given the name function-1 in Cloud Run.

    • YOUR_REGION: the Google Cloud region where you want to deploy your function. For example, europe-west1.

    • YOUR_RUNTIME: the language your function uses. For a list of supported runtimes, see Runtime support.

    • YOUR_SOURCE_LOCATION: the location of your function source code.

    • YOUR_CODE_ENTRYPOINT: the entry point to your function in your source code. This is the code that will be executed when your function runs. The value of this flag must be a function name or fully-qualified class name that exists in your source code.

For a complete reference on the functions deploy command and its flags, see the gcloud functions deploy documentation.

Triggers and retries

The following table compares triggers and retries for functions:

Cloud Run functions Cloud Run functions (1st gen)
Trigger and invoke a function For function created with the Cloud Run Admin API, you specify triggers as part of deploying the function in the Google Cloud console or after deploying the function when using the gcloud CLI.

For functions created with the Cloud Functions v2 API, you specify triggers as part of function deployment. 		You specify triggers as part of function deployment.
Event types Support for any event type supported by Eventarc, including 90+ event sources through Cloud Audit Logs. Direct support for events from 7 sources.
Retries For functions created with the Cloud Run Admin API, update the retry policy in Eventarc and configure dead-letter topic in Pub/Sub.

For functions created with the Cloud Functions v2 API, you specify retries as part of function deployment with the --retry flag. 		You specify retries as part of function deployment with the --retry flag.

Detach your function

Functions created using the Cloud Functions v2 API (for example, by using gcloud functions, the REST API, or Terraform) can be detached from its existing API environment. After you detach a function, you can only manage it using the Cloud Run Admin API. You might want to do this if your workloads need to stay within the run.googleapis.com API boundary for Assured Workloads, or to ensure that your workloads use the Cloud Run SKU. See Manage functions to learn more.

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