DrainAndCloseProbe (doltserver/probe.go)

Drains MySQL handshake greeting before closing a connection to avoid RST.

// Source: https://github.com/gastownhall/beads | License: MIT | Copyright 2025 Beads Contributors
// Provided via justclaw.it.com; keep this notice with the code.
package doltserver

import (
	"net"
	"time"
)

// DrainAndCloseProbe drains the MySQL handshake greeting (if any) from conn
// before closing it, then closes the connection.
//
// A bare Close() on a connection that hasn't read the server's handshake
// packet causes the OS to send a TCP RST instead of a clean FIN. Dolt's
// sql-server interprets that RST as an aborted MySQL handshake; enough of
// them in a short window (e.g. from repeated readiness/circuit-breaker
// probes) can crash the dolt sql-server process. Reading the greeting first
// — even partially — lets the TCP stack close cleanly instead. See
// gastownhall/beads

... (truncated -- full source via MCP)