Limitations

The following limitations and known problems apply to the 8.15.3 release of the Elastic natural language processing trained models feature.

When you use ELSER for semantic search, only the first 512 extracted tokens from each field of the ingested documents that ELSER is applied to are taken into account for the search process. If your data set contains long documents, divide them into smaller segments before ingestion if you need the full text to be searchable.

Currently, ELSER deployments do not scale up and down automatically depending on the resource requirements of the ELSER processes. If you want to configure available resources for your ELSER deployments, you can manually set the number of allocations and threads per allocation by using the Trained Models UI in Kibana or the Update trained model deployment API.