About RHAPSODY¶
RHAPSODY (Runtime for Heterogeneous APplications, Service Orchestration and DYnamism) is a cutting-edge runtime system designed to address the evolving challenges of modern scientific computing. As computational workflows become increasingly complex, combining traditional HPC simulations with AI/ML workloads, there is a critical need for systems that can efficiently orchestrate heterogeneous tasks across diverse computing resources.
Vision¶
Our vision is to create a unified runtime that seamlessly bridges the gap between traditional high-performance computing and emerging AI/ML paradigms, enabling scientists to focus on their research rather than the complexities of workflow orchestration.
Core Philosophy¶
RHAPSODY is built on several key principles:
Heterogeneity as a First-Class Citizen¶
Modern scientific workflows are inherently heterogeneous, combining:
- Traditional HPC simulations (CPU-intensive)
 - Machine learning training and inference (GPU-intensive)
 - Data processing and analysis tasks
 - I/O-intensive operations
 
RHAPSODY treats this heterogeneity as a fundamental characteristic rather than an afterthought.
Dynamic Adaptation¶
Scientific workflows are rarely static. RHAPSODY supports:
- Runtime modification of task graphs based on intermediate results
 - Adaptive resource allocation
 - Dynamic load balancing across heterogeneous resources
 
Platform Abstraction¶
Scientists should not need to be experts in every computing platform. RHAPSODY provides:
- Unified interfaces across different HPC systems
 - Abstraction of resource manager specifics
 - Portable workflow descriptions
 
Technical Innovation¶
RHAPSODY introduces several technical innovations:
Pluggable Backend Architecture¶
The system supports multiple execution backends, each optimized for different scenarios:
- Concurrent Backend: For shared-memory parallel execution
 - Dask Backend: For distributed Python workloads
 - RADICAL-Pilot Backend: For large-scale HPC execution
 
AsyncFlow Integration¶
Full compatibility with the AsyncFlow workflow management system, providing:
- Standardized workflow descriptions
 - Tool interoperability
 - Community ecosystem benefits
 
State-of-the-Art Monitoring¶
Comprehensive monitoring and introspection capabilities for:
- Real-time task execution tracking
 - Performance analysis and optimization
 - Fault detection and recovery
 
Research Impact¶
RHAPSODY enables breakthrough research in numerous domains:
- Climate Science: Coupling atmospheric simulations with ML-based post-processing
 - Materials Science: Integrating quantum simulations with ML property prediction
 - Computational Biology: Combining molecular dynamics with deep learning analysis
 
Project Timeline¶
RHAPSODY development follows a structured timeline aligned with NSF project milestones:
- Phase 1 (2021-2022): Core architecture and backend development
 - Phase 2 (2022-2024): Integration with existing workflow systems
 - Phase 3 (2024-2026): Production deployment and optimization
 
Team and Collaboration¶
RHAPSODY is developed by the RADICAL Research Team at Rutgers University, in collaboration with:
- DOE National laboratories
 - Campus supercomputing centers
 - Academic research institutions
 
Open Science Commitment¶
We are committed to open science principles:
- Open Source: All code is publicly available under MIT license
 - Open Data: Benchmarks and performance data are shared publicly
 - Open Standards: We contribute to community standards and protocols
 - Open Collaboration: We welcome contributions from the broader community
 
Future Directions¶
Looking ahead, RHAPSODY will continue to evolve to meet emerging needs:
- Enhanced support for quantum computing integration
 - Advanced AI/ML workflow optimization
 - Edge computing and IoT integration for scientific workflows
 - Expanded ecosystem of compatible tools and frameworks