Segment 8
In this sub-session, the assistant finished writing the remaining 10 improvement documents (02–11) for the local research repo, then methodically executed Tier 1 optimization tests. Piecewise CUDA graphs were blocked due to incompatibility between torch.compile(fullgraph=True) and FlashInfer FP4 JIT code; MSCCLPP and Single Batch Overlap each yielded only ~2% improvement, ruling out communication-side optimizations as transformative. The assistant then moved to Expert Parallelism (EP8) via --moe-a2a-backend flashinfer, which launched successfully with EP8 topology but was 10–14% slower at low concurrency and crashed under moderate load (256 concurrent requests). Key achievements include establishing a rigorous baseline across four concurrency levels (1, 10, 256, 1024), demonstrating that the core bottleneck remains the small per-expert GEMMs (memory-bandwidth-bound), and identifying the EP8 crash as likely due to OOM or NCCL all-to-all failures—now under investigation.
Testing the Optimization Frontier: Systematic Hypothesis Evaluation on Blackwell GPUs