Vectors

The following covers available vector model configuration options.

path

  1. path: string

Sets the path for a vectors model. When using a transformers/sentence-transformers model, this can be any model on the Hugging Face Hub or a local file path. Otherwise, it must be a local file path to a word embeddings model.

defaults

  1. defaults: boolean

Uses default vector model path when enabled (default setting is True) and path is not provided. See this link for an example.

method

  1. method: transformers|sentence-transformers|llama.cpp|litellm|external|words

Embeddings method to use. If the method is not provided, it is inferred using the path.

sentence-transformers, llama.cpp, litellm and words require the vectors extras package to be installed.

transformers

Builds embeddings using a transformers model. While this can be any transformers model, it works best with models trained to build embeddings.

Both mean and cls pooling are supported and automatically inferred from the model. The pooling method can be overwritten by changing the method from transformers to meanpooling or clspooling respectively.

Setting maxlength to True enables truncating inputs to the max_seq_length. Setting maxlength to an integer will truncate inputs to that value. When omitted (default), the maxlength will be set to either the model or tokenizer maxlength.

sentence-transformers

Same as transformers but loads models with the sentence-transformers library.

llama.cpp

Builds embeddings using a llama.cpp model. Supports both local and remote GGUF paths on the HF Hub.

litellm

Builds embeddings using a LiteLLM model. See the LiteLLM documentation for the options available with LiteLLM models.

words

Builds embeddings using a word embeddings model. Transformers models are the preferred vector backend in most cases. Word embeddings models may be deprecated in the future.

storevectors

  1. storevectors: boolean

Enables copying of a vectors model set in path into the embeddings models output directory on save. This option enables a fully encapsulated index with no external file dependencies.

pca

  1. pca: int

Removes n principal components from generated embeddings. When enabled, a TruncatedSVD model is built to help with dimensionality reduction. After pooling of vectors creates a single embedding, this method is applied.

external

Embeddings are created via an external model or API. Requires setting the transform parameter to a function that translates data into embeddings.

transform

  1. transform: function

When method is external, this function transforms input content into embeddings. The input to this function is a list of data. This method must return either a numpy array or list of numpy arrays.

gpu

  1. gpu: boolean|int|string|device

Set the target device. Supports true/false, device id, device string and torch device instance. This is automatically derived if omitted.

batch

  1. batch: int

Sets the transform batch size. This parameter controls how input streams are chunked and vectorized.

encodebatch

  1. encodebatch: int

Sets the encode batch size. This parameter controls the underlying vector model batch size. This often corresponds to a GPU batch size, which controls GPU memory usage.

dimensionality

  1. dimensionality: int

Enables truncation of vectors to this dimensionality. This is only useful for models trained to store more important information in earlier dimensions such as Matryoshka Representation Learning (MRL).

quantize

  1. quantize: int|boolean

Enables scalar vector quantization at the specified precision. Supports 1-bit through 8-bit quantization. Scalar quantization transforms continuous floating point values to discrete unsigned integers. Only the faiss, numpy and torch ANN backends support storing these vectors.

This parameter supports booleans for backwards compatability. When set to true/false, this flag sets faiss.quantize.

In addition to vector-level quantization, some ANN backends have the ability to quantize vectors at the storage layer. See the ANN configuration options for more.

instructions

  1. instructions:
  2. query: prefix for queries
  3. data: prefix for indexing

Instruction-based models use prefixes to modify how embeddings are computed. This is especially useful with asymmetric search, which is when the query and indexed data are of vastly different lengths. In other words, short queries with long documents.

E5-base is an example of a model that accepts instructions. It takes query: and passage: prefixes and uses those to generate embeddings that work well for asymmetric search.

models

  1. models: dict

Loads and stores vector models in this cache. This is primarily used with subindexes but can be set on any embeddings instance. This prevents the same model from being loaded multiple times when working with multiple embeddings instances.

tokenize

  1. tokenize: boolean

Enables string tokenization (defaults to false). This method applies tokenization rules that only work with English language text. It’s not recommended for use with recent vector models.

vectors

  1. vectors: dict

Passes these additional parameters to the underlying vector model.