perf: use f16 as split-k partial output data type #900
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If the input and output are bf16, is the accuracy still sufficient without using fp32 for partial output? |
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Hi @muoshuosha FlashMLA official implementation uses bf16 as partial output, when inputs and outputs are bf16. Here we just align with the official design. |
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As pointed out by @beginlner, flashmla uses f32 as intermediate output data type. We should make the partial O dtype a template parameter. |
MasterJH5574
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This PR applies changes in flashinfer-ai#898 and flashinfer-ai#900 to the MLA TVM binding.
yzh119
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We use f32 as split-k partial output data type, mainly for accuracy concern.
However, the official FlashMLA implementation uses 16-bit partial data type, so I guess 16bit split-k is enough for production.
This PR changes flashinfer mla implementation's intermediate data type to 16bit.
This is the third piece (4 in total) of split-k related optimizations.