Class: Cohere::Transcribe::PyTorchCheckpoint::Reader

Inherits:
Object
  • Object
show all
Defined in:
lib/cohere/transcribe/pytorch_checkpoint.rb

Overview

One checkpoint shard. Tensor bytes are never materialized as a whole.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(path) ⇒ Reader

Returns a new instance of Reader.



771
772
773
774
775
 
# File 'lib/cohere/transcribe/pytorch_checkpoint.rb', line 771

def initialize(path)
  @path = Pathname(path).expand_path
  @storages = {}
  @tensors = read_checkpoint.freeze
end

Instance Attribute Details

#path ⇒ Object (readonly)

Returns the value of attribute path.



769
770
771
 
# File 'lib/cohere/transcribe/pytorch_checkpoint.rb', line 769

def path
  @path
end

#tensors ⇒ Object (readonly)

Returns the value of attribute tensors.



769
770
771
 
# File 'lib/cohere/transcribe/pytorch_checkpoint.rb', line 769

def tensors
  @tensors
end

Instance Method Details

#fetch(name) ⇒ Object 



785
786
787
788
789
 
# File 'lib/cohere/transcribe/pytorch_checkpoint.rb', line 785

def fetch(name)
  tensors.fetch(name)
rescue KeyError
  raise Error, "Tensor #{name.inspect} is not present in #{path}"
end

#key?(name) ⇒ Boolean

Returns:

  • (Boolean) 


781
782
783
 
# File 'lib/cohere/transcribe/pytorch_checkpoint.rb', line 781

def key?(name)
  tensors.key?(name)
end

#names ⇒ Object 



777
778
779
 
# File 'lib/cohere/transcribe/pytorch_checkpoint.rb', line 777

def names
  tensors.keys
end

#write_tensor(tensor, output, target_dtype:, converter: Safetensors::DTypeConverter.default, chunk_bytes: Safetensors::DEFAULT_CHUNK_BYTES) ⇒ Object

Raises:

  • (ArgumentError) 


791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
 
# File 'lib/cohere/transcribe/pytorch_checkpoint.rb', line 791

def write_tensor(tensor, output, target_dtype:, converter: Safetensors::DTypeConverter.default,
                 chunk_bytes: Safetensors::DEFAULT_CHUNK_BYTES)
  raise ArgumentError, "Tensor #{tensor.name.inspect} belongs to a different PyTorch reader" unless tensor.reader.equal?(self)

  target_dtype = target_dtype.to_s.upcase
  unless FLOAT_DTYPES.include?(tensor.dtype) && FLOAT_DTYPES.include?(target_dtype)
    raise Error, "Cannot convert #{tensor.name.inspect} from #{tensor.dtype} to #{target_dtype}"
  end
  raise ArgumentError, "chunk_bytes must be positive" unless chunk_bytes.positive?

  source_width = Safetensors::DTYPE_BYTES.fetch(tensor.dtype)
  elements_per_chunk = [chunk_bytes / source_width, 1].max
  bytes_per_chunk = elements_per_chunk * source_width
  unless contiguous?(tensor)
    return write_strided_tensor(
      tensor, output, target_dtype: target_dtype, converter: converter,
                      elements_per_chunk: elements_per_chunk, source_width: source_width
    )
  end

  remaining = tensor.nbytes
  written = 0
  File.open(path, "rb") do |source|
    source.seek(tensor.data_start)
    while remaining.positive?
      requested = [remaining, bytes_per_chunk].min
      chunk = source.read(requested)
      raise Error, "Unexpected end of #{path} while reading #{tensor.name.inspect}" if chunk.nil? || chunk.bytesize != requested

      converted = converter.convert(chunk, from: tensor.dtype, to: target_dtype)
      output.write(converted)
      written += converted.bytesize
      remaining -= requested
    end
  end
  expected = tensor.element_count * Safetensors::DTYPE_BYTES.fetch(target_dtype)
  return written if written == expected

  raise Error, "Converted tensor #{tensor.name.inspect} wrote #{written} bytes; expected #{expected}"
end