What the data for this category looks like
Data for coal mining production service consultation and reply originates from post operation manuals, safety work regulations, equipment maintenance logs, daily inspection records, emergency response plans, and service process documents. Data sources cover multiple business links including work zone management, equipment operation and maintenance, and on-site operations, with significantly different update cycles. General work regulations are revised regularly every 1 to 2 years, while documents such as frontline inspection records and equipment logs are updated daily. Most documents follow a hierarchical structure based on work zone, equipment model, and operation steps, and include clear unit fields such as ton, cubic meter, pascal, and hour. The length of individual documents varies widely, ranging from several hundred characters of inspection records to complete work regulations with tens of thousands of characters.
What constraints these characteristics impose on vector models and indexing
The characteristics of different data types create multiple constraints for the vector models and indexing link. Newly added daily inspection and log data requires support for incremental index updates to avoid computing resource consumption caused by full reconstruction. The hierarchical structure of long documents requires retaining key metadata such as work zone and equipment model during chunking, ensuring that recall results can be associated with specific operation scenarios. The demand for multilingual Chinese and foreign language operation guides requires adaptation to multilingual embedding models to ensure recall effectiveness for cross-language service consultation. Service consultation questions mostly focus on details such as specific operation steps and parameter settings, requiring the index to match precise semantic associations.
How to set the configuration
Reference configurations under FastGPT v4.17.0 are as follows:
| Configuration Item | Recommended Setting | Rationale |
|---|---|---|
| Chunk Length | 800–1200 characters | Matches the typical single-section content length of coal mining operation documents, avoiding excessive chunking that disrupts the integrity of operation steps |
| Overlap Length | 100–150 characters | Retains cross-chunk operation process context, ensuring that complete continuous service steps can be presented during recall |
| Similarity Threshold | 0.72–0.85, calibrated via actual testing | Adapts to the semantic similarity range of coal mining professional terminology, filtering irrelevant non-corresponding post content |
| Single Search Limit | Top 6 results | Matches the typical number of results for service consultation, avoiding excessive redundant information interfering with decision-making |
defaultToken | 4096 | Adapts to the token limit for single chunks, covering the token count of most coal mining document chunks |
maxToken | 8192 | Matches the context window limit of large models, ensuring that recalled chunk content can be fully passed for processing |
Three Common Errors
- After manually uploading coal mining service documents, the interface shows that indexing has not completed for more than 4 hours. Cause: The concurrency configuration for chunk processing was not adjusted based on the volume of individual documents, and large-scale work regulations were not split to adapt to the system's processing limits.
- After replacing a multilingual embedding model, the cross-language recall effect of the existing knowledge base does not improve. Cause: A full re-embedding task was not executed, only the vectors of newly uploaded content were updated, and existing data still uses vectors generated by the old model.
- The default index generated after inserting a new document into the knowledge base disappears after several hours. Cause: The automatic cleanup cycle for temporary indexes was configured, and core indexes related to service consultation were not set to persistent storage.
How to Confirm the Configuration Is Correct
- A typical coal mining inspection record document is uploaded, and the chunked content is verified to retain key field information such as work zone and equipment model.
- A service consultation question targeting a specific post is submitted, and the returned recall results are checked for inclusion of the operation process content corresponding to that post.
- After replacing the embedding model, a full re-embedding task is executed, and the task progress is verified to complete as expected without errors.
- The index persistence configuration is viewed, and it is confirmed that the indexes for core service documents do not have automatic cleanup rules set.
The values provided are common starting points and should be measured against the reader's own samples.
Question material comes from public community discussions. Configuration values are common starting points and should be measured against your own samples. Verified on 2026-09-28.