Persistent to Hasql

[Cmdv]

Hasql Migration

Summary

The migration from Persistent to Hasql delivered a 3-4x performance improvement in epoch processing time, with some gains in cache efficiency.

Processing Time Comparison

Before (Persistent)

• Epoch 432: 29 minutes
• Epoch 433: 32 minutes
• Average: ~30.5 minutes per epoch

After (Hasql)

• Epoch 441: 8m 14s
• Epoch 442: 9m 19s
• Average: ~8.7 minutes per epoch

Improvement: 73% reduction in processing time (3.5x faster)

Resource Utilisation

Database Connections

• Before: ORM connection pooling with abstraction overhead
• After: Direct PostgreSQL connection management
• Benefit: Reduced connection overhead and more efficient resource usage

Technical Factors Contributing to Performance

1. Eliminated ORM Overhead

• No runtime type reflection
• No query generation overhead
• Direct SQL statement preparation

2. Optimised SQL Generation

• Hand-crafted SQL statements
• Better query plans
• Reduced parsing overhead

3. Type-Safe Operations

• Compile-time validation reduces runtime checks
• Efficient encoder/decoder patterns
• Zero-copy data transformations where possible

4. Connection Management

• Direct PostgreSQL protocol usage
• Reduced middleware layers
• Better connection reuse

Epoch Context

Based on Cardano network data, each epoch processes approximately 21,600 blocks over a 5-day period. The performance improvement scales linearly with blockchain growth, making this migration critical for long-term sustainability.

Conclusion

The Hasql migration represents a significant infrastructure improvement, providing both immediate performance gains and better long-term scalability. The 73% reduction in processing time, positions the system for handling increased blockchain throughput.