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:
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Running ML workloads across multiple clouds (AWS, GCP, Azure, etc.)
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Need cost optimization with automatic cloud/region selection
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Running long jobs on spot instances with auto-recovery
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Managing distributed multi-node training
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Want unified interface for 20+ cloud providers
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Need to avoid vendor lock-in
Key features:
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Multi-cloud: AWS, GCP, Azure, Kubernetes, Lambda, RunPod, 20+ providers
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Cost optimization: Automatic cheapest cloud/region selection
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Spot instances: 3-6x cost savings with automatic recovery
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Distributed training: Multi-node jobs with gang scheduling
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Managed jobs: Auto-recovery, checkpointing, fault tolerance
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Sky Serve: Model serving with autoscaling
Use alternatives instead:
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Modal: For simpler serverless GPU with Python-native API
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RunPod: For single-cloud persistent pods
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Kubernetes: For existing K8s infrastructure
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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
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Advanced Usage - Multi-cloud, optimization, production patterns
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Troubleshooting - Common issues and solutions
Resources
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Documentation: https://docs.skypilot.co
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Slack: https://slack.skypilot.co
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Examples: https://github.com/skypilot-org/skypilot/tree/master/examples