Segment 68

In this sub-session, the assistant executed a comprehensive optimization campaign for DeepSeek-V4-Flash on 8× RTX PRO 6000 Blackwell GPUs. First, custom MMA sparse-MLA decode kernels with split-K parallelization and bf16 tensor-core operations were implemented, delivering 2.2–2.9× throughput improvement. After confirming torch.compile incompatibility, profiling revealed the indexer torch fallback was computing over the full max context every decode step, causing ~69% GPU time. Capping context-length to 8192 delivered a dramatic 17.9× improvement at C=64, and a capture-safe Triton indexer kernel with early-exit per page was built for long-context support. NCCL all-reduce was confirmed at the PCIe floor, and MTP/EAGLE integration was blocked by an MXFP4 MoE routing issue. PD disaggregation was deployed on all 8 GPUs with systemd services, KV capacity was maxed to 2.58M tokens, and the chat template and reasoning parser were fixed. A full Prometheus/Grafana monitoring stack was set up from scratch with a 17-panel KV-cache dashboard. Quality issues were resolved by fixing harness mismatches, enabling thinking by default, setting server defaults, and writing a comprehensive engineering report (DSV4_SM120_REPORT.md).

Design and implement custom MMA sparse-MLA decode kernel with split-K parallelizationFlip FP32 indexer bmm and MHC-pre linear to bf16 tensor-core operationsProfile glue operations to identify remaining bottlenecksFix indexer O(max_context) bottleneck by capping context-length to 8192Build capture-safe Triton indexer kernel with early-exit per pageConfirm NCCL all-reduce at PCIe floor, no further optimization possibleAttempt MTP/EAGLE integration and diagnose MXFP4 MoE routing barrierDeploy PD disaggregation on 8 GPUs with systemd servicesMax KV capacity to 2.58M tokens at 512K contextFix missing chat template and reasoning parser for correct outputSet up Prometheus and Grafana monitoring stack from scratchConfigure scraping of metrics endpoints and provision KV-cache dashboard with 17 panelsResolve agent-coherence and tool-calling failures by fixing harness mismatchesEnable thinking by default and set server defaults (model name, temperature)Write comprehensive engineering report DSV4_SM120_REPORT.md

The Full-Stack Optimization of DeepSeek-V4-Flash on Blackwell GPUs: From 11 to 531 Tokens Per Second 4199 words

Chunks