Develop an application on the Ray cluster on Vertex AI

You can connect to a Ray cluster on Vertex AI and develop an application using the following methods:

  • Connect to the Ray cluster on Vertex AI using the version of the Vertex AI SDK for Python that includes the functionality of the Ray Client. Use this option if you prefer an interactive Python development environment.

    • Use the Vertex AI SDK for Python within the Colab Enterprise notebook in the Google Cloud console.

    • Use the Vertex AI SDK for Python within a Python session, shell, or Jupyter notebook.

  • Write a Python script and submit the script to the Ray cluster on Vertex AI using the Ray Jobs API. Use this option if you'd rather submit jobs programmatically.

Before you begin, make sure to read the Ray on Vertex AI overview and set up all the prerequisite tools you need.

Develop an application using the Vertex AI SDK for Python

To connect to the Ray cluster on Vertex AI using the Vertex AI SDK for Python, the connecting environment must be on the same peered VPC network.

Console

  1. In the Google Cloud console, go to the Ray on Vertex AI page.

    Go to the Ray on Vertex AI page

  2. In the row for the cluster you created, Click Open in Colab Enterprise.

  3. The Colab Enterprise notebook opens. Follow the instructions on how to use the Vertex AI SDK for Python to connect to the Ray cluster on Vertex AI.

    • If a dialog screen asks you to enable APIs, click Enable.

    • Click Connect if you're connecting to the cluster for the first time, or Re-connect if you're re-connecting to the cluster. The notebook takes a few minutes to connect to the Runtime.

    • Run the Getting started code cell to import the Vertex AI SDK for Python and connect to the Ray cluster on Vertex AI.

Python

From an interactive Python environment:

import ray

# Necessary even if aiplatform.* symbol is not directly used in your program.
from google.cloud import aiplatform
import vertex_ray

# The CLUSTER_RESOURCE_NAME is the one returned from vertex_ray.create_ray_cluster.
CLUSTER_RESOURCE_NAME='projects/{}/locations/{}/persistentResources/{}'.format(PROJECT_ID, REGION, CLUSTER_NAME)

ray.init('vertex_ray://{}'.format(CLUSTER_RESOURCE_NAME))

Where:

  • REGION: The region you specified for your Ray cluster on Vertex AI.

  • PROJECT_ID: Your Google Cloud project ID. You can find the project ID in the Google Cloud console welcome page.

  • CLUSTER_NAME: The name of your Ray cluster on Vertex AI, specified when you created the cluster.

You should get output similar to the following:

Python version:  3.10.12
Ray version: 2.9
Vertex SDK version: 1.46.0
Dashboard: xxxx-dot-us-central1.aiplatform-training.googleusercontent.com

You can use the Dashboard URL to access the Ray dashboard from a browser. The URI is in the format of https://xxxx-dot-us-central1.aiplatform-training.googleusercontent.com/. The dashboard shows submitted jobs, the number of GPU or CPUs, and disk space of each machine in the cluster.

Once you're connected to the Ray cluster on Vertex AI you can develop a Ray program the same way you would develop one for a normal OSS Ray backend.

@ray.remote
def square(x):
  print(x)
  return x * x

# Launch four parallel square tasks.
futures = [square.remote(i) for i in range(4)]

print(ray.get(futures))
# Returns [0, 1, 4, 9]

Develop an application using the Ray Jobs API

This section describes how to submit a Python program to the Ray cluster on Vertex AI using the Ray Jobs API.

Write a Python script

Develop your application as a Python script in any text editor. For example, place the following script in a my_script.py file:

import ray
import time

@ray.remote
def hello_world():
    return "hello world"

@ray.remote
def square(x):
    print(x)
    time.sleep(100)
    return x * x

ray.init()  # No need to specify address="vertex_ray://...."
print(ray.get(hello_world.remote()))
print(ray.get([square.remote(i) for i in range(4)]))

Submit a Ray job using the Ray Jobs API

You can submit a Ray job using Python, the Ray Jobs CLI, or the public Ray dashboard address.

Python - cluster resource name

Within the VPC peered network, submit a Ray job using a Python environment:

import ray
import vertex_ray
from ray.job_submission import JobSubmissionClient
from google.cloud import aiplatform  # Necessary even if aiplatform.* symbol is not directly used in your program.

CLUSTER_RESOURCE_NAME='projects/{}/locations/REGION/persistentResources/{}'.format(PROJECT_ID, CLUSTER_NAME)

client = JobSubmissionClient("vertex_ray://{}".format(CLUSTER_RESOURCE_NAME))

job_id = client.submit_job(
  # Entrypoint shell command to execute
  entrypoint="python my_script.py",
  # Path to the local directory that contains the my_script.py file.
  runtime_env={
    "working_dir": "./directory-containing-my-script",
    "pip": ["numpy",
            "xgboost",
            "ray==2.9.3", # pin the Ray version to prevent it from being overwritten
           ]
  }
)

# Ensure that the Ray job has been created.
print(job_id)

Where:

  • REGION: The region you specified for your Ray cluster on Vertex AI.

  • PROJECT_ID: Your Google Cloud project number. You can find the project ID in the Google Cloud console welcome page.

  • CLUSTER_NAME: The name of your Ray cluster on Vertex AI, specified when you created the cluster.

Python - Ray dashboard

The Ray dashboard address is accessible from outside the VPC, including the public internet. Note that vertex_ray is required to obtain authentication automatically.

from ray.job_submission import JobSubmissionClient
import vertex_ray

DASHBOARD_ADDRESS=DASHBOARD_ADDRESS

client = JobSubmissionClient(
  "vertex_ray://{}".format(DASHBOARD_ADDRESS),
)

job_id = client.submit_job(
  # Entrypoint shell command to execute
  entrypoint="python my_script.py",
  # Path to the local directory that contains the my_script.py file
  runtime_env={
    "working_dir": "./directory-containing-my-script",
    "pip": ["numpy",
            "xgboost",
            "ray==2.9.3", # pin the Ray version to prevent it from being overwritten
           ]
  }
)
print(job_id)

Where:

DASHBOARD_ADDRESS: The Ray dashboard address for your cluster. You can find the dashboard address using the Vertex AI SDK for Python.

Ray Jobs CLI

Note that you can only use the Ray Jobs CLI commands within the peered VPC network.

$ ray job submit --working-dir ./ --address vertex_ray://{CLUSTER_RESOURCE_NAME} -- python my_script.py

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