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TENSOR_ALIGNMENT

Constant TENSOR_ALIGNMENT 

Source
pub const TENSOR_ALIGNMENT: u64 = 256;
Expand description

Alignment for tensor data in bytes.

All tensor data is aligned to 256-byte boundaries to enable efficient memory-mapped (mmap) zero-copy loading. This alignment ensures:

  • Proper pointer alignment for all tensor element types (f64 requires 8-byte alignment)
  • Cache-line friendly access (most CPUs use 64-byte cache lines)
  • GPU memory alignment (CUDA prefers 256-byte for coalesced access)
  • Future-proofing for wider SIMD (AVX-512 = 64 bytes, future AVX-1024 = 128 bytes)

Industry alignment choices:

  • 256-byte: GGUF, MLX, ncnn, MNN, TNN, vLLM-AWQ, Marlin (15+ formats)
  • 64-byte: SafeTensors (minimum for AVX-512)
  • 4096-byte: Core ML

256-byte alignment has negligible overhead for typical tensor sizes while providing maximum compatibility with current and future hardware.