OpenSearch provides a variety of open-source pretrained models that can assist with a range of machine learning (ML) search and analytics use cases. You can upload any supported model to the OpenSearch cluster and use it locally.
This example uses a simple setup with no dedicated ML nodes and allows running a model on a non-ML node.
On clusters with dedicated ML nodes, specify `"only_run_on_ml_node": "true"` for improved performance. For more information, see [ML Commons cluster settings]({{site.url}}{{site.baseurl}}/ml-commons-plugin/cluster-settings/).
To ensure that this basic local setup works, specify the following cluster settings:
```json
PUT _cluster/settings
{
"persistent": {
"plugins": {
"ml_commons": {
"only_run_on_ml_node": "false",
"model_access_control_enabled": "true",
"native_memory_threshold": "99"
}
}
}
}
```
{% include copy-curl.html %}
## Step 1: Register a model group
To register a model, you have the following options:
- You can use `model_group_id` to register a model version to an existing model group.
- If you do not use `model_group_id`, ML Commons creates a model with a new model group.
To register a model group, send the following request:
```json
POST /_plugins/_ml/model_groups/_register
{
"name": "local_model_group",
"description": "A model group for local models"
}
```
{% include copy-curl.html %}
The response contains the model group ID that you'll use to register a model to this model group:
```json
{
"model_group_id": "wlcnb4kBJ1eYAeTMHlV6",
"status": "CREATED"
}
```
To learn more about model groups, see [Model access control]({{site.url}}{{site.baseurl}}/ml-commons-plugin/model-access-control/).
## Step 2: Register a local OpenSearch-provided model
To register a remote model to the model group created in step 1, provide the model group ID from step 1 in the following request.
Because pretrained **sentence transformer** models originate from the ML Commons model repository, you only need to provide the `name`, `version`, `model_group_id`, and `model_format` in the upload API request:
"description": "This is a neural sparse encoding model: It transfers text into sparse vector, and then extract nonzero index and value to entry and weights. It serves only in ingestion and customer should use tokenizer model in query.",
You can find the `url` and `model_content_hash_value` in the model config link for each model. For more information, see the [Supported pretrained models section](#supported-pretrained-models). Set the `function_name` to `SPARSE_ENCODING` or `SPARSE_TOKENIZE`.
Note that the `function_name` parameter in the request corresponds to the `model_task_type` parameter in the model config. When using a pretrained model, make sure to change the name of the parameter from `model_task_type` to `function_name` in the model upload request.
OpenSearch returns the task ID of the register operation:
```json
{
"task_id": "cVeMb4kBJ1eYAeTMFFgj",
"status": "CREATED"
}
```
To check the status of the operation, provide the task ID to the [Tasks API]({{site.url}}{{site.baseurl}}/ml-commons-plugin/api/tasks-apis/get-task/#get-a-task-by-id):
```bash
GET /_plugins/_ml/tasks/cVeMb4kBJ1eYAeTMFFgj
```
{% include copy-curl.html %}
When the operation is complete, the state changes to `COMPLETED`:
```json
{
"model_id": "cleMb4kBJ1eYAeTMFFg4",
"task_type": "REGISTER_MODEL",
"function_name": "REMOTE",
"state": "COMPLETED",
"worker_node": [
"XPcXLV7RQoi5m8NI_jEOVQ"
],
"create_time": 1689793598499,
"last_update_time": 1689793598530,
"is_async": false
}
```
Take note of the returned `model_id` because you’ll need it to deploy the model.
## Step 3: Deploy the model
The deploy operation reads the model's chunks from the model index and then creates an instance of the model to load into memory. The bigger the model, the more chunks the model is split into and longer it takes for the model to load into memory.
To deploy the registered model, provide its model ID from step 3 in the following request:
```bash
POST /_plugins/_ml/models/cleMb4kBJ1eYAeTMFFg4/_deploy
```
{% include copy-curl.html %}
The response contains the task ID that you can use to check the status of the deploy operation:
```json
{
"task_id": "vVePb4kBJ1eYAeTM7ljG",
"status": "CREATED"
}
```
As in the previous step, check the status of the operation by calling the Tasks API:
```bash
GET /_plugins/_ml/tasks/vVePb4kBJ1eYAeTM7ljG
```
{% include copy-curl.html %}
When the operation is complete, the state changes to `COMPLETED`:
```json
{
"model_id": "cleMb4kBJ1eYAeTMFFg4",
"task_type": "DEPLOY_MODEL",
"function_name": "REMOTE",
"state": "COMPLETED",
"worker_node": [
"n-72khvBTBi3bnIIR8FTTw"
],
"create_time": 1689793851077,
"last_update_time": 1689793851101,
"is_async": true
}
```
## Step 4 (Optional): Test the model
Use the [Predict API]({{site.url}}{{site.baseurl}}/ml-commons-plugin/api/train-predict/predict/) to test the model.
For a text embedding model, send the following request:
```json
POST /_plugins/_ml/_predict/text_embedding/cleMb4kBJ1eYAeTMFFg4
{
"text_docs":[ "today is sunny"],
"return_number": true,
"target_response": ["sentence_embedding"]
}
```
{% include copy-curl.html %}
The response contains text embeddings for the provided sentence:
```json
{
"inference_results" : [
{
"output" : [
{
"name" : "sentence_embedding",
"data_type" : "FLOAT32",
"shape" : [
768
],
"data" : [
0.25517133,
-0.28009856,
0.48519906,
...
]
}
]
}
]
}
```
For a sparse encoding model, send the following request:
```json
POST /_plugins/_ml/_predict/sparse_encoding/cleMb4kBJ1eYAeTMFFg4
To learn how to set up a vector index and use text embedding models for search, see [Semantic search]({{site.url}}{{site.baseurl}}/search-plugins/semantic-search/).
To learn how to set up a vector index and use sparse encoding models for search, see [Sparse search]({{site.url}}{{site.baseurl}}/search-plugins/sparse-search/).
OpenSearch supports the following models, categorized by type. Text embedding models are sourced from [Hugging Face](https://huggingface.co/). Sparse encoding models are trained by OpenSearch. Although models with the same type will have similar use cases, each model has a different model size and will perform differently depending on your cluster setup. For a performance comparison of some pretrained models, see the [SBERT documentation](https://www.sbert.net/docs/pretrained_models.html#model-overview).
Sentence transformer models map sentences and paragraphs across a dimensional dense vector space. The number of vectors depends on the type of model. You can use these models for use cases such as clustering or semantic search.
The following table provides a list of sentence transformer models and artifact links you can use to download them. Note that you must prefix the model name with `huggingface/`, as shown in the **Model name** column.
| Model name | Version | Vector dimensions | Auto-truncation | TorchScript artifact | ONNX artifact |
Sparse encoding models transfer text into a sparse vector and convert the vector to a list of `<token: weight>` pairs representing the text entry and its corresponding weight in the sparse vector. You can use these models for use cases such as clustering or sparse neural search.
| Model name | Auto-truncation | TorchScript artifact | Description |
|---|---|---|
| `amazon/neural-sparse/opensearch-neural-sparse-encoding-v1` | Yes | - [model_url](https://artifacts.opensearch.org/models/ml-models/amazon/neural-sparse/opensearch-neural-sparse-encoding-v1/1.0.0/torch_script/opensearch-neural-sparse-encoding-v1-1.0.0-torch_script.zip)<br>- [config_url](https://artifacts.opensearch.org/models/ml-models/amazon/neural-sparse/opensearch-neural-sparse-encoding-v1/1.0.0/torch_script/config.json) | A neural sparse encoding model. The model transforms text into a sparse vector, identifies the indexes of non-zero elements in the vector, and then converts the vector into `<entry, weight>` pairs, where each entry corresponds to a non-zero element index. |
| `amazon/neural-sparse/opensearch-neural-sparse-encoding-doc-v1` | Yes | - [model_url](https://artifacts.opensearch.org/models/ml-models/amazon/neural-sparse/opensearch-neural-sparse-encoding-doc-v1/1.0.0/torch_script/opensearch-neural-sparse-encoding-doc-v1-1.0.0-torch_script.zip)<br>- [config_url](https://artifacts.opensearch.org/models/ml-models/amazon/neural-sparse/opensearch-neural-sparse-encoding-doc-v1/1.0.0/torch_script/config.json) | A neural sparse encoding model. The model transforms text into a sparse vector, identifies the indexes of non-zero elements in the vector, and then converts the vector into `<entry, weight>` pairs, where each entry corresponds to a non-zero element index. |
| `amazon/neural-sparse/opensearch-neural-sparse-tokenizer-v1` | Yes | - [model_url](https://artifacts.opensearch.org/models/ml-models/amazon/neural-sparse/opensearch-neural-sparse-tokenizer-v1/1.0.0/torch_script/opensearch-neural-sparse-tokenizer-v1-1.0.0.zip)<br>- [config_url](https://artifacts.opensearch.org/models/ml-models/amazon/neural-sparse/opensearch-neural-sparse-tokenizer-v1/1.0.0/torch_script/config.json) | A neural sparse tokenizer model. The model tokenizes text into tokens and assigns each token a predefined weight, which is the token's IDF (if the IDF file is not provided, the weight defaults to 1). For more information, see [Preparing a model]({{site.url}}{{site.baseurl}}/ml-commons-plugin/custom-local-models/#preparing-a-model). |
