Instant Cloning
Piglet Run supports Copy-on-Write (CoW) cloning for rapid database forking.
How It Works
Copy-on-Write means:
- Zero copy at clone time
- Only changed blocks consume storage
- TB-scale databases clone in milliseconds
Original Database
┌─────────────────────┐
│ Block A │ Block B │ Block C │
└────┬────┴────┬────┴────┬────┘
│ │ │
▼ ▼ ▼
┌────────────────────────────┐
│ Shared Storage │
└────────────────────────────┘
▲ ▲ ▲
│ │ │
┌────┴────┬────┴────┬────┴────┐
│ Block A │ Block B │ Block C │ (shared)
│ │ Block B'│ │ (changed in clone)
└─────────┴─────────┴─────────┘
Cloned Database
Use Cases
| Use Case | Benefit |
|---|---|
| Development | Clone prod for testing |
| AI Experiments | Branch for each experiment |
| Feature Branches | Database per branch |
| Training | Each learner gets own copy |
Database Cloning
Using PostgreSQL utilities:
# Create database from template
pig pg psql -c "CREATE DATABASE dev TEMPLATE prod"
# Or using pg_dump/pg_restore for cross-server clone
pg_dump -Fc prod > prod.dump
pg_restore -d dev prod.dump
Using pgBackRest for Cloning
# Restore to a new cluster as a clone
pig pb restore --target-pgdata=/data/pg-clone
# Or restore to specific time point
pig pb restore -t "2025-01-29 10:00:00" --target-pgdata=/data/pg-clone
Filesystem Cloning with JuiceFS
# Clone directory using JuiceFS snapshot
juicefs snapshot create /jfs/workspace ws-snapshot
juicefs snapshot restore /jfs/workspace-clone ws-snapshot
Next Steps
- See Clone Task
- Learn about Snapshots