初始化
main
|-mysqld
|-my_init // 初始话线程变量，互斥量
|-load_defaults // 获得配置
|-init_common_variables // 初始化变量
|-init_server_components // 初始化插件
| |-plugin_init
| | |-plugin_initialize
| |-initialize_storage_engine
|-network_init // 监听网络
|-grant_init
|-servers_init
|-udf_init
插件启动
main
|-mysqld_main
|-init_server_components
|-plugin_init
|-plugin_initialize
|-ha_initialize_handlerton
|-innobase_init
登录进程
main
|-mysqld_main
|-network_init // 建立socket监听，1个针对网络，1个针对unix域
|-handle_connections_sockets
|-poll
|-mysql_socket_accept // 和客户端建立连接
|-create_new_thread // 针对每一个socket连接建立1个新的线程
|-create_thread_to_handle_connection
|-waiting_thd_list->push_back(thd);mysql_cond_signal(&COND_thread_cache); // 已有连接处理线程时，通过信号唤醒，处理线程函数为pfs_spawn_thread
|-mysql_thread_create(启动的线程履行函数，inline_mysql_thread_create)
|-spawn_thread_v1
|-pthread_create(pfs_spawn_thread)
处理连接
pfs_spawn_thread
|-handle_one_connection
|-do_handle_one_connection
|-MYSQL_CALLBACK_ELSE(thread_scheduler, init_new_connection_thread, (), 0)
| |-init_new_connection_handler_thread
|-thd_prepare_connection
| |-login_connection // 判断是不是可以login，不可以则断开连接返回毛病
| | |-check_connection
| | | |-acl_authenticate
| | | |-do_auth_once
| | | |-native_password_authenticate
| | | |-server_mpvio_write_packet
| | | | |-send_server_handshake_packet // 发送handshake包到客户端
| | | | |-my_net_write
| | | | | |-net_write_buff // 将数据写入到内存
| | | | |-net_flush // 将内存中数据发送到网络
| | | |-server_mpvio_read_packet // 从客户端接收Login Request信息
| | | |-my_net_read
| | |-Protocol::end_statement
| | |-Protocol::send_ok
| | |-net_send_ok // 发送response ok
| | |-my_net_write
| |-prepare_new_connection_state
|-do_command
|-dispatch_command
|-mysql_parse
处理命令select
pfs_swpawn_thread
|-handle_one_connection
|-do_handle_one_connection
|-do_command
|-dispatch_command
|-mysql_parse
|-parse_sql
| |-MYSQLparse
|-mysql_execute_command
|-select_precheck
| |-check_table_access
|-execute_sqlcom_select
| |-open_normal_and_derived_tables
| |-open_tables
| | |-open_and_process_table
| | |-open_table(THD *thd, TABLE_LIST *table_list, Open_table_context *ot_ctx)
| | |-Table_cache::get_table
| | |-get_table_share_with_discover
| | | |-get_table_share
| | | |-open_table_def
| | |-my_malloc // 申请表数据结构
| | |-open_table_from_share
| | |-handler::ha_open
| | |-ha_innobase::open
| | |-dict_table_open_on_name
| | |-dict_load_table
| | |-btr_pcur_is_on_user_rec
| | |-dict_load_table_low
| | | |-dict_mem_table_create
| | |-fil_space_for_table_exists_in_mem
| | |-fil_open_single_table_tablespace // 打开表空间文件
| |-mysql_handle_derived
|-handle_select
|-mysql_select
|-mysql_prepare_select
| |-JOIN::prepare
|-mysql_execute_select
|-JOIN::exec
|-select_send::send_result_set_metadata
| |-Protocol::send_result_set_metadata
|-do_select
|-sub_select
|-evaluate_join_record
|-end_send
|-select_send::send_data
|-Protocol::write