Chunk 9.0

## Summary In this chunk, the assistant systematically executed the next wave of optimization work after the research agents returned findings. Key actions included: **updating sglang** to the latest commit (which alone yielded a **2x throughput improvement at 256 concurrency** vs earlier baselines), **implementing Opportunistic Expert Activation (OEA)** as a decode-time routing optimization (gated by `SGLANG_OEA_K0` env var), and **retrying Expert Parallelism (EP8) with a memory-safe config** (`--mem-fraction-static 0.75 --max-running-requests 512`). The OEA implementation was carefully engineered to handle the unsorted top-k output and use proper sigmoid scores for weight gathering, but clean A/B benchmarks showed **near-zero average throughput improvement** on random data (though peak throughput improved ~5% at high concurrency), confirming that OEA's benefit depends on non-uniform expert routing patterns. EP8 loaded successfully with the reduced memory config (59.5GB used, ~34GB free per GPU) but crashed during warmup due to CUTLASS tile failures (128×256×128 exceeding SM120's 100KB shared memory limit), though the server ultimately recovered and ran. The assistant also **benchmarked concurrency 1 and 2** (10.36 tok/s single-stream, 19.29 tok/s dual-stream — excellent linear scaling), **wrote the comprehensive `glm5findings.md` document** (500+ lines covering all discoveries, benchmarks, and lessons learned), and **began computing the theoretical maximum single-stream performance** for this exact model/hardware combination. The theoretical analysis was in progress when the chunk ended, with the assistant gathering model config parameters to compute HBM bandwidth-limited and PCIe allreduce-limited throughput ceilings. The overarching theme is a methodical, evidence-based optimization campaign: each idea is implemented, benchmarked cleanly against baseline, documented, and either adopted or ruled out based on real measurements rather than speculation.

The Methodical Campaign: How Evidence-Based Optimization Drove a 2x Throughput Breakthrough on Blackwell GPUs 2566 words

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