⚡ GPU Kernel Speed • FlashAttention-3 • Hopper H100 FP8 • Memory Bandwidth
FlashAttention-3 Throughput & TFLOPS Calibrator
Understand how kernel tiling and asynchronous tensor memory accelerators (TMA) unlock 700+ TFLOPS on NVIDIA H100 GPUs during LLM prefill and decoding.
Workload Configuration
Context Sequence Length (N) 16,384 tokens
Batch Size 4
💡 FlashAttention-3 Innovation
FA3 overlaps Gemini Tensor Cores (GEMM) with asynchronous softmax calculations in GPU SRAM, preventing arithmetic pipelines from stalling on memory reads.
Kernel Throughput Comparison
2.2x Faster than FA2| Attention Implementation | Effective TFLOPS | HBM Reads/Writes | Relative Latency |
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Production vLLM / SGLang Flag Configuration