SkyPilot Multi-Cloud Orchestration

Comprehensive guide to running ML workloads across clouds with automatic cost optimization using SkyPilot.

When to use SkyPilot

Use SkyPilot when:

Running ML workloads across multiple clouds (AWS, GCP, Azure, etc.)
Need cost optimization with automatic cloud/region selection
Running long jobs on spot instances with auto-recovery
Managing distributed multi-node training
Want unified interface for 20+ cloud providers
Need to avoid vendor lock-in

Key features:

Multi-cloud: AWS, GCP, Azure, Kubernetes, Lambda, RunPod, 20+ providers
Cost optimization: Automatic cheapest cloud/region selection
Spot instances: 3-6x cost savings with automatic recovery
Distributed training: Multi-node jobs with gang scheduling
Managed jobs: Auto-recovery, checkpointing, fault tolerance
Sky Serve: Model serving with autoscaling

Use alternatives instead:

Modal: For simpler serverless GPU with Python-native API
RunPod: For single-cloud persistent pods
Kubernetes: For existing K8s infrastructure
Ray: For pure Ray-based orchestration

Quick start

Installation

pip install "skypilot[aws,gcp,azure,kubernetes]"

# Verify cloud credentials
sky check

Hello World

Create hello.yaml:

resources:
  accelerators: T4:1

run: |
  nvidia-smi
  echo "Hello from SkyPilot!"

Launch:

sky launch -c hello hello.yaml

# SSH to cluster
ssh hello

# Terminate
sky down hello

Core concepts

Task YAML structure

# Task name (optional)
name: my-task

# Resource requirements
resources:
  cloud: aws              # Optional: auto-select if omitted
  region: us-west-2       # Optional: auto-select if omitted
  accelerators: A100:4    # GPU type and count
  cpus: 8+                # Minimum CPUs
  memory: 32+             # Minimum memory (GB)
  use_spot: true          # Use spot instances
  disk_size: 256          # Disk size (GB)

# Number of nodes for distributed training
num_nodes: 2

# Working directory (synced to ~/sky_workdir)
workdir: .

# Setup commands (run once)
setup: |
  pip install -r requirements.txt

# Run commands
run: |
  python train.py

Key commands

| Command | Purpose | |---------|---------| | sky launch | Launch cluster and run task | | sky exec | Run task on existing cluster | | sky status | Show cluster status | | sky stop | Stop cluster (preserve state) | | sky down | Terminate cluster | | sky logs | View task logs | | sky queue | Show job queue | | sky jobs launch | Launch managed job | | sky serve up | Deploy serving endpoint |

GPU configuration

Available accelerators

# NVIDIA GPUs
accelerators: T4:1
accelerators: L4:1
accelerators: A10G:1
accelerators: L40S:1
accelerators: A100:4
accelerators: A100-80GB:8
accelerators: H100:8

# Cloud-specific
accelerators: V100:4         # AWS/GCP
accelerators: TPU-v4-8       # GCP TPUs

GPU fallbacks

resources:
  accelerators:
    H100: 8
    A100-80GB: 8
    A100: 8
  any_of:
    - cloud: gcp
    - cloud: aws
    - cloud: azure

Spot instances

resources:
  accelerators: A100:8
  use_spot: true
  spot_recovery: FAILOVER  # Auto-recover on preemption

Cluster management

Launch and execute

# Launch new cluster
sky launch -c mycluster task.yaml

# Run on existing cluster (skip setup)
sky exec mycluster another_task.yaml

# Interactive SSH
ssh mycluster

# Stream logs
sky logs mycluster

Autostop

resources:
  accelerators: A100:4
  autostop:
    idle_minutes: 30
    down: true  # Terminate instead of stop

# Set autostop via CLI
sky autostop mycluster -i 30 --down

Cluster status

# All clusters
sky status

# Detailed view
sky status -a

Distributed training

Multi-node setup

resources:
  accelerators: A100:8

num_nodes: 4  # 4 nodes × 8 GPUs = 32 GPUs total

setup: |
  pip install torch torchvision

run: |
  torchrun \
    --nnodes=$SKYPILOT_NUM_NODES \
    --nproc_per_node=$SKYPILOT_NUM_GPUS_PER_NODE \
    --node_rank=$SKYPILOT_NODE_RANK \
    --master_addr=$(echo "$SKYPILOT_NODE_IPS" | head -n1) \
    --master_port=12355 \
    train.py

Environment variables

| Variable | Description | |----------|-------------| | SKYPILOT_NODE_RANK | Node index (0 to num_nodes-1) | | SKYPILOT_NODE_IPS | Newline-separated IP addresses | | SKYPILOT_NUM_NODES | Total number of nodes | | SKYPILOT_NUM_GPUS_PER_NODE | GPUs per node |

Head-node-only execution

run: |
  if [ "${SKYPILOT_NODE_RANK}" == "0" ]; then
    python orchestrate.py
  fi

Managed jobs

Spot recovery

# Launch managed job with spot recovery
sky jobs launch -n my-job train.yaml

Checkpointing

name: training-job

file_mounts:
  /checkpoints:
    name: my-checkpoints
    store: s3
    mode: MOUNT

resources:
  accelerators: A100:8
  use_spot: true

run: |
  python train.py \
    --checkpoint-dir /checkpoints \
    --resume-from-latest

Job management

# List jobs
sky jobs queue

# View logs
sky jobs logs my-job

# Cancel job
sky jobs cancel my-job

File mounts and storage

Local file sync

workdir: ./my-project  # Synced to ~/sky_workdir

file_mounts:
  /data/config.yaml: ./config.yaml
  ~/.vimrc: ~/.vimrc

Cloud storage

file_mounts:
  # Mount S3 bucket
  /datasets:
    source: s3://my-bucket/datasets
    mode: MOUNT  # Stream from S3

  # Copy GCS bucket
  /models:
    source: gs://my-bucket/models
    mode: COPY  # Pre-fetch to disk

  # Cached mount (fast writes)
  /outputs:
    name: my-outputs
    store: s3
    mode: MOUNT_CACHED

Storage modes

| Mode | Description | Best For | |------|-------------|----------| | MOUNT | Stream from cloud | Large datasets, read-heavy | | COPY | Pre-fetch to disk | Small files, random access | | MOUNT_CACHED | Cache with async upload | Checkpoints, outputs |

Sky Serve (Model Serving)

Basic service

# service.yaml
service:
  readiness_probe: /health
  replica_policy:
    min_replicas: 1
    max_replicas: 10
    target_qps_per_replica: 2.0

resources:
  accelerators: A100:1

run: |
  python -m vllm.entrypoints.openai.api_server \
    --model meta-llama/Llama-2-7b-chat-hf \
    --port 8000

# Deploy
sky serve up -n my-service service.yaml

# Check status
sky serve status

# Get endpoint
sky serve status my-service

Autoscaling policies

service:
  replica_policy:
    min_replicas: 1
    max_replicas: 10
    target_qps_per_replica: 2.0
    upscale_delay_seconds: 60
    downscale_delay_seconds: 300
  load_balancing_policy: round_robin

Cost optimization

Automatic cloud selection

# SkyPilot finds cheapest option
resources:
  accelerators: A100:8
  # No cloud specified - auto-select cheapest

# Show optimizer decision
sky launch task.yaml --dryrun

Cloud preferences

resources:
  accelerators: A100:8
  any_of:
    - cloud: gcp
      region: us-central1
    - cloud: aws
      region: us-east-1
    - cloud: azure

Environment variables

envs:
  HF_TOKEN: $HF_TOKEN  # Inherited from local env
  WANDB_API_KEY: $WANDB_API_KEY

# Or use secrets
secrets:
  - HF_TOKEN
  - WANDB_API_KEY

Common workflows

Workflow 1: Fine-tuning with checkpoints

name: llm-finetune

file_mounts:
  /checkpoints:
    name: finetune-checkpoints
    store: s3
    mode: MOUNT_CACHED

resources:
  accelerators: A100:8
  use_spot: true

setup: |
  pip install transformers accelerate

run: |
  python train.py \
    --checkpoint-dir /checkpoints \
    --resume

Workflow 2: Hyperparameter sweep

name: hp-sweep-${RUN_ID}

envs:
  RUN_ID: 0
  LEARNING_RATE: 1e-4
  BATCH_SIZE: 32

resources:
  accelerators: A100:1
  use_spot: true

run: |
  python train.py \
    --lr $LEARNING_RATE \
    --batch-size $BATCH_SIZE \
    --run-id $RUN_ID

# Launch multiple jobs
for i in {1..10}; do
  sky jobs launch sweep.yaml \
    --env RUN_ID=$i \
    --env LEARNING_RATE=$(python -c "import random; print(10**random.uniform(-5,-3))")
done

Debugging

# SSH to cluster
ssh mycluster

# View logs
sky logs mycluster

# Check job queue
sky queue mycluster

# View managed job logs
sky jobs logs my-job

Common issues

| Issue | Solution | |-------|----------| | Quota exceeded | Request quota increase, try different region | | Spot preemption | Use sky jobs launch for auto-recovery | | Slow file sync | Use MOUNT_CACHED mode for outputs | | GPU not available | Use any_of for fallback clouds |

References

Advanced Usage - Multi-cloud, optimization, production patterns
Troubleshooting - Common issues and solutions

Resources

Documentation: https://docs.skypilot.co
GitHub: https://github.com/skypilot-org/skypilot
Slack: https://slack.skypilot.co
Examples: https://github.com/skypilot-org/skypilot/tree/master/examples

skypilot-multi-cloud-orchestration

SkyPilot Multi-Cloud Orchestration

When to use SkyPilot

Quick start

Installation

Hello World

Core concepts

Task YAML structure

Key commands

GPU configuration

Available accelerators

GPU fallbacks

Spot instances

Cluster management

Launch and execute

Autostop

Cluster status

Distributed training

Multi-node setup

Environment variables

Head-node-only execution

Managed jobs

Spot recovery

Checkpointing

Job management

File mounts and storage

Local file sync

Cloud storage

Storage modes

Sky Serve (Model Serving)

Basic service

Autoscaling policies

Cost optimization

Automatic cloud selection

Cloud preferences

Environment variables

Common workflows

Workflow 1: Fine-tuning with checkpoints

Workflow 2: Hyperparameter sweep

Debugging

Common issues

References

Resources