Why Automate ML Pipeline Retraining
Machine learning models degrade over time as data distributions change—a phenomenon called model drift. Automating retraining ensures:
Fresh models: Models are updated regularly with the latest data.
Consistency: Standardized preprocessing, training, evaluation, and deployment steps.
Scalability: Pipelines can handle large datasets without manual intervention.
Cloud Composer allows you to schedule and orchestrate these ML workflows in a cloud-native, reproducible way.
๐ Components of an ML Retraining Pipeline
A typical retraining pipeline includes:
Data extraction and preprocessing
Collect new data from databases, storage, or streaming sources.
Perform cleaning, feature engineering, and transformations.
Model training
Train a new model on updated data.
Track hyperparameters, metrics, and artifacts.
Model evaluation
Validate new model against test data.
Compare performance with the currently deployed model.
Model deployment (optional)
If the new model passes evaluation, deploy to production (e.g., Cloud AI Platform, Cloud Functions, or serving endpoints).
Monitoring & alerting
Track model performance over time.
Trigger alerts if retrained models fail evaluation criteria.
๐ Implementing ML Retraining in Cloud Composer
Step 1: Create a DAG
from airflow import DAG
from airflow.utils.dates import days_ago
from airflow.operators.python import PythonOperator
default_args = {
'owner': 'airflow',
'depends_on_past': False,
'retries': 1,
}
with DAG(
dag_id='ml_pipeline_retraining',
default_args=default_args,
start_date=days_ago(1),
schedule_interval='@weekly', # Retrain weekly
catchup=False
) as dag:
def extract_and_preprocess():
# Code to fetch new data and preprocess
print("Extracting and preprocessing data...")
def train_model():
# Training code here
print("Training new ML model...")
def evaluate_model():
# Evaluate performance, compare with current model
print("Evaluating new model...")
def deploy_model():
# Deploy if performance is satisfactory
print("Deploying model to production...")
t1 = PythonOperator(task_id='extract_preprocess', python_callable=extract_and_preprocess)
t2 = PythonOperator(task_id='train_model', python_callable=train_model)
t3 = PythonOperator(task_id='evaluate_model', python_callable=evaluate_model)
t4 = PythonOperator(task_id='deploy_model', python_callable=deploy_model)
t1 >> t2 >> t3 >> t4
Step 2: Parameterize DAG for Flexibility
Use Airflow Variables or DAG parameters for:
Data sources or table names
Training hyperparameters
Deployment targets
Example with Variable:
from airflow.models import Variable
data_path = Variable.get("ml_data_path", default_var="gs://my-bucket/data/")
Step 3: Use GCP Services for Scaling
Cloud Storage: Store datasets and model artifacts.
AI Platform / Vertex AI: Train and deploy large models.
BigQuery: Use for feature extraction or large datasets.
Cloud Functions or Cloud Run: Trigger retraining jobs dynamically.
Example: Triggering Vertex AI training job:
from airflow.providers.google.cloud.operators.vertex_ai import (
VertexAiCustomJobRunOperator
)
train_vertex_job = VertexAiCustomJobRunOperator(
task_id="vertex_ai_training",
project_id="my-project",
location="us-central1",
body={
"display_name": "ml_training_job",
"job_spec": {
"worker_pool_specs": [
{
"machine_spec": {"machine_type": "n1-standard-4"},
"replica_count": 1,
"python_package_spec": {
"executor_image_uri": "gcr.io/cloud-aiplatform/training/tf-cpu.2-8:latest",
"package_uris": ["gs://my-bucket/ml_code.tar.gz"],
"python_module": "trainer.task",
},
}
]
},
}
)
Step 4: Monitoring & Logging
Airflow DAG logs show workflow execution.
Use Vertex AI or Cloud Logging to track model metrics, evaluation, and deployment logs.
Consider adding email or Slack alerts if retraining fails.
Step 5: Best Practices
Schedule retraining frequency wisely
Weekly, daily, or triggered by new data availability.
Avoid retraining too often unless model drift is rapid.
Use versioning for models
Store models with timestamps or version IDs in Cloud Storage or Vertex AI.
Automate evaluation and rollback
Only deploy if the new model improves or maintains performance.
Keep previous model as fallback.
Handle secrets securely
Use Secret Manager for database credentials, API keys, or service account keys.
Test DAG locally or in dev environment
Avoid accidentally retraining in production with untested code.
๐ Summary
Cloud Composer enables automated, reproducible ML retraining pipelines.
A typical workflow: extract → preprocess → train → evaluate → deploy → monitor.
Parameterize DAGs, integrate with GCP services (Vertex AI, Cloud Storage, BigQuery), and enforce secure handling of secrets.
Monitoring, evaluation thresholds, and rollback mechanisms are key to safe automation.
Learn GCP Training in Hyderabad
Read More
Automating Cloud Function Deployments with Composer
Managing Secrets in Cloud Composer Workflows
Triggering Cloud Run Jobs from Composer DAGs
Visit Our Quality Thought Training Institute in Hyderabad
Subscribe by Email
Follow Updates Articles from This Blog via Email
No Comments