Ray를 사용하여 애플리케이션 확장하기¶

import ray
import numpy as np
import pandas as pd
from sklearn.linear_model import LinearRegression

# Initialize Ray (automatically connects to cluster in Snowflake ML)
ray.init(address="auto", ignore_reinit_error=True)

# Create sample data
large_dataset = np.random.randn(1000, 10)
batch_data = pd.DataFrame(np.random.randn(100, 5), columns=[f'feature_{i}' for i in range(5)])

# Ray Tasks - stateless remote functions
@ray.remote
def compute_heavy_task(data):
    """CPU-intensive computation example"""
    # Simulate heavy computation (matrix operations)
    result = np.dot(data, data.T)
    return np.mean(result)

# Ray Actors - stateful remote classes
@ray.remote
class DataProcessor:
    def __init__(self):
        # Load a simple model
        self.model = LinearRegression()
        # Train on dummy data
        X_dummy = np.random.randn(100, 5)
        y_dummy = np.random.randn(100)
        self.model.fit(X_dummy, y_dummy)

    def process_batch(self, batch):
        # Convert to numpy if it's a DataFrame
        if isinstance(batch, pd.DataFrame):
            batch_array = batch.values
        else:
            batch_array = batch
        return self.model.predict(batch_array)

# Submit tasks and get object references
future = compute_heavy_task.remote(large_dataset)
result = ray.get(future)  # Blocks until task completes
print(f"Task result: {result}")

# Create and use actors
processor = DataProcessor.remote()
batch_result = ray.get(processor.process_batch.remote(batch_data))
print(f"Batch processing result shape: {batch_result.shape}")

import ray
import ray.data as rd
import pandas as pd
import numpy as np
from snowflake.ml.runtime_cluster import scale_cluster

# Initialize Ray
ray.init(address="auto", ignore_reinit_error=True)

# Optional: Scale cluster for better performance with large datasets or CPU-intensive operations
# Scaling benefits Ray Data when:
# - Processing datasets larger than single-node memory (>10GB)
# - Performing CPU-intensive transformations (complex feature engineering, ML preprocessing)
# - Need faster processing through parallelization across multiple nodes
scale_cluster(expected_cluster_size=4)

# Create sample dataset
np.random.seed(42)
n_samples = 50000
n_features = 15

# Generate features with some correlation structure
base_features = np.random.randn(n_samples, 5)
derived_features = np.column_stack([
    base_features[:, 0] * base_features[:, 1],  # interaction
    np.sin(base_features[:, 2]),  # non-linear
    base_features[:, 3] ** 2,  # polynomial
    np.random.randn(n_samples, n_features - 8)  # additional random features
])

X = np.column_stack([base_features, derived_features])
y = (X[:, 0] + 0.5 * X[:, 1] - 0.3 * X[:, 2] + 0.1 * X[:, 5] + np.random.randn(n_samples) * 0.2 > 0).astype(int)

sample_data = pd.DataFrame(X, columns=[f'feature_{i}' for i in range(n_features)])
sample_data['target'] = y

print(f"Created dataset with {n_samples} samples and {n_features} features")

# Create Ray Dataset from pandas DataFrame
ray_dataset = rd.from_pandas(sample_data)

# Transform data with Ray Data operations
def preprocess_batch(batch):
    """Preprocess a batch of data"""
    # Get all feature columns
    feature_cols = [col for col in batch.columns if col.startswith('feature_')]

    # Normalize numerical features (first 3 for demo)
    for col in feature_cols[:3]:
        if col in batch.columns:
            batch[f'{col}_scaled'] = (batch[col] - batch[col].mean()) / batch[col].std()

    # Add derived features using actual column names
    if 'feature_0' in batch.columns and 'feature_1' in batch.columns:
        batch['feature_0_squared'] = batch['feature_0'] ** 2
        batch['feature_interaction'] = batch['feature_0'] * batch['feature_1']

    return batch

# Apply transformations lazily
processed_dataset = ray_dataset.map_batches(
    preprocess_batch,
    batch_format="pandas"
)

# Repartition for optimal performance across cluster nodes
processed_dataset = processed_dataset.repartition(num_blocks=8)

# Convert to different formats for downstream use
print("Converting to pandas...")
pandas_df = processed_dataset.to_pandas()  # Collect to pandas
print(f"Processed dataset shape: {pandas_df.shape}")
print(f"New columns: {list(pandas_df.columns)}")

# Iterate through batches for memory efficiency
print("Processing batches...")
batch_count = 0
for batch in processed_dataset.iter_batches(batch_size=1000, batch_format="pandas"):
    batch_count += 1
    print(f"Batch {batch_count}: {batch.shape}")
    if batch_count >= 3:  # Just show first 3 batches
        break

print(f"Total batches processed: {batch_count}")

import ray
from ray import tune
import pandas as pd
import numpy as np
from sklearn.ensemble import RandomForestClassifier
from sklearn.model_selection import train_test_split
from sklearn.metrics import accuracy_score
from snowflake.ml.runtime_cluster import scale_cluster

# Initialize Ray
ray.init(address="auto", ignore_reinit_error=True)

# Optional: Scale cluster for hyperparameter tuning
# Scaling benefits Ray Tune when:
# - Running many trials in parallel
# - Each trial is computationally intensive
# - Need faster hyperparameter search
scale_cluster(expected_cluster_size=6)

# Create sample dataset
np.random.seed(42)
n_samples = 5000
n_features = 10

X = np.random.randn(n_samples, n_features)
y = ((X[:, 0] + X[:, 1] * X[:, 2] + np.sin(X[:, 3]) + np.random.randn(n_samples) * 0.3) > 0).astype(int)

# Split data
X_train, X_val, y_train, y_val = train_test_split(X, y, test_size=0.2, random_state=42)

def train_function(config):
    """Training function that gets hyperparameters from Ray Tune"""
    # Train model with current hyperparameters
    model = RandomForestClassifier(
        n_estimators=config["n_estimators"],
        max_depth=config["max_depth"],
        min_samples_split=config["min_samples_split"],
        random_state=42,
        n_jobs=-1
    )

    model.fit(X_train, y_train)

    # Evaluate and report results
    val_predictions = model.predict(X_val)
    accuracy = accuracy_score(y_val, val_predictions)

    # Report metrics back to Ray Tune
    return {"accuracy": accuracy}

# Define search space
search_space = {
    "n_estimators": tune.randint(50, 200),
    "max_depth": tune.randint(3, 15),
    "min_samples_split": tune.randint(2, 10)
}

# Configure and run hyperparameter optimization
tuner = tune.Tuner(
    tune.with_resources(
        train_function,
        resources={"CPU": 2}
    ),
    param_space=search_space,
    tune_config=tune.TuneConfig(
        metric="accuracy",
        mode="max",
        num_samples=20,  # Number of trials
        max_concurrent_trials=4
    )
)

print("Starting hyperparameter optimization...")
results = tuner.fit()

# Get best results
best_result = results.get_best_result()
print(f"✅ Hyperparameter tuning completed!")
print(f"   Best accuracy: {best_result.metrics['accuracy']:.4f}")
print(f"   Best parameters: {best_result.config}")

# Show results summary
df_results = results.get_dataframe()
print(f"\nTop 5 results:")
top_results = df_results.nlargest(5, 'accuracy')
for i, (_, row) in enumerate(top_results.iterrows(), 1):
    print(f"  {i}. Accuracy: {row['accuracy']:.4f}, n_estimators: {row['config/n_estimators']}, max_depth: {row['config/max_depth']}")

import ray
from ray.job_submission import JobSubmissionClient
import os

# Initialize Ray and get job client
ray.init(address="auto", ignore_reinit_error=True)

# Get Ray dashboard address for job submission
node_ip = os.getenv("NODE_IP_ADDRESS", "0.0.0.0")
dashboard_port = os.getenv("DASHBOARD_PORT", "9999")
dashboard_address = f"http://{node_ip}:{dashboard_port}"

client = JobSubmissionClient(dashboard_address)

# Simple job script
job_script = '''
import ray

@ray.remote
def compute_task(x):
    return x * x

# Submit tasks to Ray cluster
futures = [compute_task.remote(i) for i in range(5)]
results = ray.get(futures)
print(f"Results: {results}")
'''

# Submit job
job_id = client.submit_job(
    entrypoint=f"python -c '{job_script}'",
    runtime_env={"pip": ["numpy"]},
    submission_id="my-ray-job"
)

print(f"Submitted job: {job_id}")

# Monitor job status
status = client.get_job_status(job_id)
print(f"Job status: {status}")

import ray
from snowflake.ml.runtime_cluster import get_nodes
from snowflake.ml.runtime_cluster.cluster_manager import (
    get_available_cpu, get_available_gpu, get_num_cpus_per_node
)

# Check available resources
available_cpus = get_available_cpu()
available_gpus = get_available_gpu()
cpus_per_node = get_num_cpus_per_node()

print(f"Available CPUs: {available_cpus}")
print(f"Available GPUs: {available_gpus}")
print(f"CPUs per node: {cpus_per_node}")

# Get Ray's view of resources
ray_resources = ray.available_resources()
print(f"Ray available resources: {ray_resources}")

# Calculate resource utilization
total_cpus = ray.cluster_resources().get('CPU', 0)
used_cpus = total_cpus - available_cpus
utilization = (used_cpus / total_cpus * 100) if total_cpus > 0 else 0
print(f"CPU Utilization: {utilization:.1f}%")