Kubernetes GPU Autoscaling: Why LLM Inference Stalls

GPU autoscaling on Kubernetes breaks for LLM inference because the Horizontal Pod Autoscaler cannot see accelerators and the node layer takes minutes to add one. The fix is a four-layer stack — DCGM exporter, Prometheus Adapter, HPA, and KEDA over Karpenter — because better GPU allocation sharpens placement without touching …

Attention-FFN Disaggregation: MoE Inference’s Next Step

Attention-FFN disaggregation (AFD) is the next architectural split beyond prefill-decode disaggregation for large mixture-of-experts (MoE) models: it separates the attention modules from the feed-forward expert modules onto distinct GPU pools inside the decode phase, fusing the extra activation transfer with the all-to-all dispatch that MoE expert parallelism already requires. The …

Tuning vLLM KV Cache and Preemption in Production Serving

vLLM’s PagedAttention and iteration-level continuous batching are the two mechanisms that take an autoregressive transformer from the 20–40% GPU utilization typical under static batching toward the 2–4× throughput the SOSP 2023 paper reports. Production value does not come from enabling them — both are on by default — but from …

Model Distillation: 32B Beats o1-Mini at Half the Cost

A 32-billion-parameter student model fine-tuned on DeepSeek-R1’s reasoning traces scored 72.6% Pass@1 on AIME 2024, beating OpenAI’s o1-mini (63.6%) while costing roughly an order of magnitude less per token to serve. Released with the DeepSeek-R1 checkpoints, it is the strongest production evidence yet that knowledge distillation—not larger GPUs—is the dominant …

LLM Inference Nondeterminism: Why Temperature 0 Fails You

LLM inference nondeterminism means identical prompts can return different outputs even at temperature 0, because dynamic batching changes the order of floating-point reductions inside GPU kernels — a property called batch invariance. Thinking Machines Lab measured 80 distinct completions from 1,000 identical requests on Qwen3-235B, and researchers documented up to …

CUDA Graphs + torch.compile: 1.65x LLM Decode Speedup

A single decode step for Llama 3.1 8B on an H100 SXM5 takes 8.4 milliseconds in eager mode. Capture that same forward pass as a CUDA graph and it drops to 5.1 milliseconds — a 1.65× speedup. The reason is not faster math; it is the elimination of CPU-side kernel-launch …

NVIDIA NIM Savings: When Self-Hosting Beats LLM APIs

A single NVIDIA H100 GPU running a self-hosted NIM container costs roughly $1,950 per month on RunPod at $2.69 per hour, yet serves the same OpenAI-compatible /v1/chat/completions endpoint as GPT-4.1 — which bills $6 per million blended tokens. The crossover where NIM beats every per-token API sits around 300–500 million …

Continuous Batching: Why 60% of Your GPU Sits Idle

Naive static batching leaves roughly 60% of an H100 GPU idle during LLM serving, because finished requests hold their slots until the slowest sequence in the batch completes. Continuous batching — iteration-level scheduling introduced in the Orca paper and now the default in vLLM, TensorRT-LLM and TGI — fixes this …

Prefill-Decode Disaggregation: NVIDIA’s 7x Inference Fix

Every LLM inference request is two workloads pretending to be one. Prefill processes your entire prompt in a single compute-bound forward pass — it wants raw FP8 TFLOPS. Decode generates tokens one at a time by streaming KV cache tensors through memory — it wants HBM bandwidth. Running both on …

Prefill Decode Disaggregation Doubles Your LLM Throughput

Prefill-decode disaggregation separates the two phases of LLM inference — prompt processing and token generation — onto dedicated GPU pools, eliminating the head-of-line blocking that causes latency spikes under concurrent load. Production deployments report 1.5x to 2.5x throughput gains, with cache-aware variants like Together AI’s CPD pushing improvements to 40%. …

vLLM vs SGLang: Which Engine Actually Wins in 2026?

On H100 SXM5 80GB running Llama 3.3 70B Instruct at FP8, SGLang serves 1,920 tokens per second at 50-way concurrency — just 3.8% faster than vLLM’s 1,850. But swap to Llama 3.1 8B, and that gap explodes to 29%: SGLang hits 16,200 tok/s versus vLLM’s 12,500. The inference engine you …

Serverless GPU Cold Starts Take 40s – Here’s How to Fix

The 1000x Latency Gap A cold-start instance on a serverless GPU platform produces its first token after more than 40 seconds. A warm instance generates subsequent tokens in roughly 30 milliseconds. That is a latency ratio of over 1,300:1 between the cold and warm states, and it is the single …