Skip to main content
Enterprise AI Analysis: HPC-R1: Characterizing R1-like Large Reasoning Models on HPC

Enterprise AI Analysis

HPC-R1: Characterizing R1-like Large Reasoning Models on HPC

This paper details HPC-R1, a comprehensive characterization of Large Reasoning Model (LRM) training on the NERSC Perlmutter supercomputer. It highlights significant challenges in reproducibility, efficiency, and system-level optimization for complex LRM training workflows. The study identifies key system inefficiencies and scaling behaviors across SFT, GRPO-based RL, autoregressive generation, and distillation stages, offering 19 key observations and recommendations for future HPC-AI system design. The findings emphasize the need for optimized communication, improved GPU utilization, sufficient CPU memory, and adaptive software stacks to better support LRM training workloads.

Key Executive Impact

Our analysis reveals quantifiable advantages for enterprise AI adoption:

0x Communication Speedup with OFI Plugin
0 Key Observations Across LRM Stages
0B Maximum LRM Model Parameters Analyzed

Deep Analysis & Enterprise Applications

Select a topic to dive deeper, then explore the specific findings from the research, rebuilt as interactive, enterprise-focused modules.

HPC Systems
AI Workloads
Distributed Training

Insight: GPU Underutilization During Generation

0% GPU utilization during LRM generation averages only 44% due to communication overhead and memory-bound decode phases, indicating significant underutilization of expensive hardware.

Resource Requirements Across Training Stages

Stage Minimum Required GPUs Key Challenges
SFT 4 (70B model)
  • Communication overhead, network backend optimization critical.
RL-GRPO 64 (70B model)
  • CPU memory bottleneck, low communication-computation overlap.
Generation 8 (70B model)
  • KV Cache limitations, GPU underutilization.
Distillation (Large Model) 32 (671B R1)
  • Generation is the primary bottleneck, requires high GPU count.
Distillation (Small Model) 1 (1B/3B Llama)
  • SFT is efficient, but monitoring training loss is crucial to avoid divergence.

Harnessing Slingshot Interconnect for LRM Training

Problem: Traditional interconnects often bottleneck large-scale distributed AI training due to high communication latency and low bandwidth, especially for collective operations.

Solution: Perlmutter's Slingshot interconnect with the OFI plugin drastically reduces communication overhead during SFT training, improving throughput by up to 7.16x compared to standard TCP/IP. This significantly speeds up communication-intensive phases.

Impact: The enhanced interconnect performance directly contributes to more efficient scaling of LRM training, reducing overall iteration time and making large models more feasible on HPC systems. However, configuring and optimizing it correctly remains a challenge.

Keywords: Slingshot, OFI Plugin, Communication Efficiency, SFT Training, HPC Interconnects

Enterprise Process Flow

Cold Start Mitigation (SFT)
Enhancing Reasoning (GRPO-RL)
SFT with Synthesized Data
Generalization & Improvement (GRPO-RL)
Distillation Generation
Distillation SFT

Insight: Ideal SFT Weak Scaling

0 TFLOPS/GPU SFT exhibits ideal weak scaling, maintaining nearly constant compute efficiency (9.80 TFLOPS/GPU) across various GPU scales, demonstrating effective aggregated throughput with increasing data parallelism.

Insight: RL Communication Bottleneck

0% AllReduce operations dominate communication time at larger DP scales in RL, consuming over 65% of each iteration, indicating a communication bottleneck for large-scale RL training.

Advanced ROI Calculator

Estimate the potential return on investment for integrating AI solutions into your operations.

Estimated Annual Savings $0
Annual Hours Reclaimed 0

Tailored Implementation Roadmap

Our phased approach ensures a smooth and effective integration of advanced AI into your enterprise.

Phase 1: Discovery & Strategy

Comprehensive analysis of your existing infrastructure, data, and business objectives. We define clear AI strategies and success metrics tailored to your needs.

Phase 2: Pilot & Integration

Development and deployment of a proof-of-concept. Iterative testing and refinement ensure seamless integration with your current systems and workflows.

Phase 3: Scaling & Optimization

Full-scale deployment across your enterprise. Continuous monitoring, performance tuning, and new feature integration drive ongoing value and innovation.

Ready to Revolutionize Your Enterprise with AI?

Connect with our experts to discuss how these insights can transform your business. Book a complimentary session today.

Ready to Get Started?

Book Your Free Consultation.

Let's Discuss Your AI Strategy!

Lets Discuss Your Needs


AI Consultation Booking