MySQL啟動的服務程序是mysqld。

mysqld -- The MySQL server daemon
Usage: mysqld [OPTIONS]
The MySQL server daemon processes requests from clients, such as:
- Accepting incoming connections from clients that communicate using
a variety of protocols (for example, HTTP, X Protocol, MySQL Protocol).
- Reading client requests for data or action and returning the results.
- Processing user-defined statements or queries and returning results.
- Managing storage of and access to data in databases.
The mysqld program has many configurable options and settings that determine
how it operates, such as:
- where it looks for data files to serve clients
- how it authenticates users who want to access the server
- how it allocates and manages memory resources
- how it logs information, errors, and performance statistics
For more information, see the MySQL Reference Manual, which includes:
- "The MySQL Server",
https://dev.mysql.com/doc/refman/8.0/en/mysql.html
- "Using MySQL Programs",
https://dev.mysql.com/doc/refman/8.0/en/programs-overview.html
- "Server Configuration Options",
https://dev.mysql.com/doc/refman/8.0/en/server-options.html
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.

啟動mysqld服務時，可以使用命令行工具或者系統服務管理器。在命令行中，可以使用以下命令啟動MySQL：

$ sudo systemctl start mysqld

在Windows系統中，可以使用服務管理器來啟動mysqld服務。

總之，mysqld服務是MySQL的核心組件，它負責處理來自客戶端的請求，并管理數據庫的存儲和訪問。