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