NVIDIA / NVIDIA/CUDALibrarySamples
LtMxfp8matmul tflops issue
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@rsdubtso is already working on this.
Since Sep 10, 2025.
cuBLASLt
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Description
Hi, I just use the example LtMxfp8Matmul in 5090, when I test 4096x4096x4096 matmul case, in only use 210+us, we can compute the tflops around 600+TFLOPs, but 5090 peak fp8 tlops is 419, is there something wrong?
the kernel name is:
cutlass3x_sm120_bstensorop_s16832gemm_block_scaled_ue8m0xe4m3_ue8m0xe4m3_f32_bf16_ue8m0xe4m3_128x128x128_1x1x1_0_tnn_align16_q_bias_bf16_relu_epiVs32n
I think the accumulate type should be fp32 right?....
PS: I get this profile result by using Nsight system
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