Intermittent Disconnect When Inserting Small LONGBLOB/Text Values (< 8192 Bytes)

When inserting AI-generated embedding data into a LONGBLOB (or equivalent) column, the MariaDB server occasionally and unpredictably closes the client connection if the payload size is below approximately 8192 bytes.

This behavior is intermittent — for example, when processing ~1000 documents, roughly 1-2 inserts may fail due to a server disconnect. The issue does not occur if the inserted payload is padded so that its size exceeds 8192 bytes.

The disconnect occurs during the insert operation and is not accompanied by a reproducible error message in the client. No corresponding error is consistently logged on the server side.

Observed Behavior:

Occurs only with payload sizes < 8192 bytes.

Inconsistent; may happen once in several hundred to thousand insert operations.

When the disconnect happens, the client connection is dropped mid-insert.

No SQL syntax issues; only data size appears correlated.

Expected Behavior:

Inserts of any valid size within the column's limit should succeed without causing unexpected connection termination.

Steps to Reproduce:

Create a table with a LONGBLOB or similar binary column.

Insert binary data (AI embeddings) of varying sizes, including some payloads < 8192 bytes.

Run inserts in bulk (hundreds to thousands of operations).

Observe occasional connection drops on small payload sizes.

Workaround:

Padding the payload to a size > 8192 bytes prevents the disconnect.

Environment:

MariaDB version: [12.0.1-MariaDB]

Storage engine: [InnoDB]

OS: [Windows version]

Client library: [langchain_mariadb python]

Max packet size: [768 Dimensions]