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Optimize GPU execution

vllm-project/vllm
Based on 2 comments
CUDA

Ensure GPU code is optimized for both proper thread utilization and correct architecture dispatching: 1. **Maximize thread parallelism** - Design CUDA kernels to fully utilize available threads. When appropriate, use multi-dimensional grid configurations to parallelize across all relevant dimensions of your problem.

Performance Optimization CUDA

Reviewer Prompt

Ensure GPU code is optimized for both proper thread utilization and correct architecture dispatching:

  1. Maximize thread parallelism - Design CUDA kernels to fully utilize available threads. When appropriate, use multi-dimensional grid configurations to parallelize across all relevant dimensions of your problem.
// Instead of TODO comments like:
// TODO utilize more CUDA threads
// this will probably need some extra padding for warps

// Consider implementing a 2D grid approach:
dim3 block_dim(32, 8);  // Thread block dimensions
dim3 grid_dim((n + block_dim.x - 1) / block_dim.x, 
             (padded_m + block_dim.y - 1) / block_dim.y);
kernel<<<grid_dim, block_dim>>>(...);
  1. Implement proper architecture dispatching - When supporting multiple GPU architectures, combine compile-time preprocessor directives with runtime architecture detection:
// Instead of compile-time only checks:
#if defined ENABLE_CUTLASS_MOE_SM100 && ENABLE_CUTLASS_MOE_SM100
  if (version_num >= 100) {  // Use runtime version check
    cutlass_moe_mm_sm100(out_tensors, a_tensors, b_tensors, a_scales, b_scales,
                       expert_offsets, problem_sizes, a_strides, b_strides,
                       c_strides, per_act_token, per_out_ch);
    return;
  }
#endif

These approaches prevent performance bottlenecks and ensure code works correctly across different GPU hardware generations.

2
Comments Analyzed
CUDA
Primary Language
Performance Optimization
Category

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