medium severityMarqo (add_documents API, document processing pipeline)
Document addition via add_documents hangs or takes excessively long (stalls) especially for unstructured indexes; may timeout or degrade performance with large batches.
Root cause
Vespa bug (versions before 8.396.18) slows distribution of configuration files for dynamic index setting updates in unstructured indexes (Marqo 2.13.0+), causing long processing times; exacerbated by large batches exhausting resources or timeouts.
marqovespaadd_documentsunstructured-indextimeoutbatch-sizememory