Aborted connection ... (Got an error reading communication packets)

[bnchdan]

Description:
When using lua-resty-mysql with MariaDB, I see frequent warnings in syslog:

[Warning] Aborted connection … (Got an error reading communication packets)

This happens both when using db:set_keepalive(timeout, pool_size) and when using db:close() after queries.

Is this expected behavior? Are there best practices to avoid these syslog warnings while safely closing or reusing connections?