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[ft_attention] Fix for seqlen=8136 (#488)

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When seqlen=8136, `smem_sz = 48840`, and apparently starting the kernel returns an `invalid argument` CUDA error.

`48840 < 48 * 1024` but apparently it's still above the limit somehow..?
Tested on A100
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dan_the_3rd 2023-08-28 19:00:22 +02:00 committed by GitHub
parent 757058d4d3
commit c3f2a632aa
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1 changed files with 1 additions and 3 deletions
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csrc/ft_attention/decoder_masked_multihead_attention.cu
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@ -31,9 +31,7 @@
size_t smem_sz = mmha::smem_size_in_bytes<T, DO_CROSS_ATTENTION>(params, THDS_PER_VALUE, THDS_PER_BLOCK); \
auto kernel = mmha::masked_multihead_attention_kernel<T, Dh, Dh_MAX, THDS_PER_KEY, THDS_PER_VALUE, \
THDS_PER_BLOCK, DO_CROSS_ATTENTION>; \
if (smem_sz >= 48 * 1024) { \
cudaFuncSetAttribute(kernel, cudaFuncAttributeMaxDynamicSharedMemorySize, smem_sz); \
} \
dim3 grid(params.nnz_head_idx == nullptr ? params.num_heads : params.nnz_heads, params.batch_size); \
kernel<<<grid, THDS_PER_BLOCK, smem_sz, stream>>>(params)