How To Run A Ray Job#
Introduction#
All members of a project in Hopsworks can launch the following types of applications through a project's Jobs service:
- Python (Hopsworks Enterprise only)
- Apache Spark
- Ray
Launching a job of any type is very similar process, what mostly differs between job types is the various configuration parameters each job type comes with. Hopsworks support scheduling to run jobs on a regular basis, e.g backfilling a Feature Group by running your feature engineering pipeline nightly. Scheduling can be done both through the UI and the python API, checkout our Scheduling guide.
Enable Ray
Support for Ray needs to be explicitly enabled by adding the following option in the values.yaml
file for the deployment:
global:
ray:
enabled: true
UI#
Step 1: Jobs overview#
The image below shows the Jobs overview page in Hopsworks and is accessed by clicking Jobs
in the sidebar.
Step 2: Create new job dialog#
Click New Job
and the following dialog will appear.
Step 3: Set the job type#
By default, the dialog will create a Spark job. Make sure RAY
is chosen.
Step 4: Set the script#
Next step is to select the program to run. You can either select From project
, if the file was previously uploaded to Hopsworks, or Upload new file
which lets you select a file from your local filesystem as demonstrated below. After that set the name for the job. By default, the job name is the same as the file name, but you can customize it here.
Step 5 (optional): Advanced configuration#
Resource allocation for the Driver and Workers can be configured.
Using the resources in the Ray script
The resource configurations describe the cluster that will be provisioned when launching the Ray job. User can still provide extra configurations in the job script using ScalingConfig
, i.e. ScalingConfig(num_workers=4, trainer_resources={"CPU": 1}, use_gpu=True)
.
-
Driver memory
: Memory in MBs to allocate for Driver -
Driver virtual cores
: Number of cores to allocate for the Driver -
Worker memory
: Memory in MBs to allocate for each worker -
Worker cores
: Number of cores to allocate for each worker -
Min workers
: Minimum number of workers to start with -
Max workers
: Maximum number of workers to scale up to
Runtime environment and Additional files required for the Ray job can also be provided.
-
Runtime Environment (Optional)
: A runtime environment describes the dependencies required for the Ray job including files, packages, environment variables, and more. This is useful when you need to install specific packages and set environment variables for this particular Ray job. It should be provided as a YAML file. You can select the file from the project or upload a new one. -
Additional files
: List of other files required for the Ray job. These files will be placed in/srv/hops/ray/job
.
Step 6: Execute the job#
Now click the Run
button to start the execution of the job, and then click on Executions
to see the list of all executions.
Ray Dashboard#
When the Ray job is running, you can access the Ray dashboard to monitor the job. The Ray dashboard is accessible from the Executions
page. Please note that the Ray dashboard is only available when the job execution is running. In the Ray Dashboard, you can monitor the resources used by the job, the number of workers, logs, and the tasks that are running.
Step 9: Application logs#
Once the execution is finished, you can click on Logs
to see the full logs for execution.
Code#
Step 1: Upload the Ray script#
This snippet assumes the Ray program is in the current working directory and named ray_job.py
. If the file is already in the project, you can skip this step.
It will upload the jar to the Resources
dataset in your project.
import hopsworks
project = hopsworks.login()
dataset_api = project.get_dataset_api()
uploaded_file_path = dataset_api.upload("ray_job.py", "Resources")
Step 2: Create Ray job#
In this snippet we get the JobsApi
object to get the default job configuration for a RAY
job, set the python script to run and create the Job
object.
jobs_api = project.get_jobs_api()
ray_config = jobs_api.get_configuration("RAY")
ray_config['appPath'] = uploaded_file_path
ray_config['environmentName'] = "ray-training-pipeline"
ray_config['driverCores'] = 2
ray_config['driverMemory'] = 2048
ray_config['workerCores'] = 2
ray_config['workerMemory'] = 4096
ray_config['minWorkers'] = 1
ray_config['maxWorkers'] = 4
job = jobs_api.create_job("ray_job", ray_config)
Step 3: Execute the job#
In this snippet we execute the job synchronously, that is wait until it reaches a terminal state, and then download and print the logs.
execution = job.run(await_termination=True)
out, err = execution.download_logs()
f_out = open(out, "r")
print(f_out.read())
f_err = open(err, "r")
print(f_err.read())