MySQL 一个简单insert语句的大概流程

2022-07-30 23:12:20

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简单记录，可能有误，主要记录重要的接口以备后用。

一、操作说明
我建了一个简单的表，插入一个简单的数据。

Query OK, 0 rows affected (2.38 sec) mysql> insert into testin values(10);
Query OK, 1 row affected (0.02 sec)
主要跟踪这个简单的插入语句在插入过程的经历。主要集中在插入流程和提交流程，不包含前期的其他阶段。
下面是这个语句经历的所有的阶段：

126 T@2: | THD::enter_stage: 'starting' /root/mysql5.7.14/percona-server-5.7.14-7/sql/conn_handler/socket_connection.cc:100
   349 T@2: | | | | | | THD::enter_stage: 'checking permissions' /root/mysql5.7.14/percona-server-5.7.14-7/sql/auth/sql_authorization.cc:843
   359 T@2: | | | | | | | THD::enter_stage: 'Opening tables' /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_base.cc:5719 1078 T@2: | | | | | THD::enter_stage: 'init' /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_insert.cc:470
  1155 T@2: | | | | | | | THD::enter_stage: 'System lock' /root/mysql5.7.14/percona-server-5.7.14-7/sql/lock.cc:321 1253 T@2: | | | | | THD::enter_stage: 'update' /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_insert.cc:663
  1535 T@2: | | | | | THD::enter_stage: 'end' /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_insert.cc:881 1544 T@2: | | | | THD::enter_stage: 'query end' /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5174 1603 T@2: | | | | THD::enter_stage: 'closing tables' /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5252 1730 T@2: | | | THD::enter_stage: 'freeing items' /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5855
  1793 T@2: | | THD::enter_stage: 'cleaning up' /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1884
  1824 T@2: | THD::enter_stage: 'starting' /root/mysql5.7.14/percona-server-5.7.14-7/sql/conn_handler/socket_connection.cc:100
主要集中在：

update
query end
两个阶段

二、大概流程
1、乐观插入的流程
Sql_cmd_insert::mysql_insert
>Sql_cmd_insert::mysql_insert
    >切换session状态为 update
    >进入插入逻辑
    >handler::ha_write_row
     >ha_innobase::write_row
      >row_insert_for_mysql
            >row_insert_for_mysql_using_ins_graph
             >trx_start_if_not_started_xa_low
               >trx_start_low                                       激活事物，事物状态由 not_active 变为 active
             >row_ins_step
               >row_ins
                >row_ins_index_entry_step
                 >row_ins_index_entry
                  >row_ins_clust_index_entry
                            >row_ins_clust_index_entry_low
                              >btr_cur_search_to_nth_level                   查找定位数据
                               >btr_cur_optimistic_insert                    进行乐观插入
                                 >btr_cur_ins_lock_and_undo
                                  >trx_undo_report_row_operation
                                    >trx_undo_page_report_insert               记录insert的undo记录
                                     >trx_undo_page_set_next_prev_and_add
                                      >trx_undof_page_add_undo_rec_log         记录undo的redo log 入redo buffer
                                 >page_cur_tuple_insert                      进行insert 元组插入，及实际的插入操作
                                  >page_cur_insert_rec_write_log             记录插入的redo log 入redo buffer
       >binlog_log_row
        >write_locked_table_maps
         >THD::binlog_write_table_map
          >binlog_start_trans_and_stmt
           >binlog_cache_data::write_event                        binlog event 写入到 binlog cache
2、其提交流程
进入提交逻辑
mysql_execute_command
>切换session状态为 query end >trans_commit_stmt
  >ha_commit_trans
   >MYSQL_BIN_LOG::prepare
    >ha_prepare_low
       >binlog_prepare                                         生成last_commit
     >innobase_xa_prepare
      >trx_prepare_for_mysql
       >trx_prepare                                            转换事物状态为，事物状态由 active 变为 prepare
   >MYSQL_BIN_LOG::commit
    >MYSQL_BIN_LOG::ordered_commit
     >MYSQL_BIN_LOG::process_flush_stage_queue
      >ha_flush_logs
       >plugin_foreach_with_mask
        >flush_handlerton
         >innobase_flush_logs
          >log_buffer_flush_to_disk
           >log_write_up_to
            >log_group_write_buf                               innodb 组提交，确保redo落盘
      >MYSQL_BIN_LOG::flush_thread_caches
       >binlog_cache_mngr::flush
        >binlog_cache_data::flush                              binlog cache 进行flush到binlog文件
      >MYSQL_BIN_LOG::sync_binlog_file                         fsync binlog文件进行os缓存落盘
      >MYSQL_BIN_LOG::process_commit_stage_queue
       >ha_commit_low
        >innobase_commit
         >innobase_commit_low
          >trx_commit_in_memory                                innodb 进行提交,事物状态由 prepare 变为 not_active
可以看到整个语句的流程大概为

会话状态转换为update
激活事物状态由 not_active 变为 active
查找定位数据
进行乐观插入
记录insert的undo记录
记录undo的redo log 入redo buffer
进行insert 元组插入，及实际的插入操作
记录插入的redo log 入redo buffer
binlog event 写入到 binlog cache
会话状态转换为query end
进入提交准备
binlog准备
innodb层事物准备，状态由 active变为 prepare
进入提交阶段
innodb进行组提交，确保redo落盘
binlog cache 进行flush到binlog文件
fsync binlog文件进行os缓存落盘
innodb 进行提交,事物状态由 prepare 变为 not_active
这只是大概流程其中很多很多的细节，不过有了入口函数也许好分析一些。

三、备用栈帧
Num     Type           Disp Enb Address            What 1 breakpoint     keep y 0x0000000000ebd5f3 in main(int, char**) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/main.cc:25 breakpoint already hit 1 time 5 breakpoint     keep y 0x0000000001a90776 in page_cur_insert_rec_write_log(rec_t*, ulint, rec_t*, dict_index_t*, mtr_t*)
                                              at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/page/page0cur.cc:964 breakpoint already hit 7 times 8 breakpoint     keep y 0x0000000001bc8f96 in trx_undo_page_report_insert(ib_page_t*, trx_t*, dict_index_t*, dtuple_t const*, mtr_t*)
                                              at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0rec.cc:478 breakpoint already hit 5 times 9 breakpoint     keep y 0x0000000001bc84c4 in trx_undof_page_add_undo_rec_log(ib_page_t*, ulint, ulint, mtr_t*)
                                              at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0rec.cc:67 breakpoint already hit 20 times 10 breakpoint     keep y 0x00000000019a932d in innobase_start_trx_and_assign_read_view(handlerton*, THD*)
                                              at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:4499 11 breakpoint     keep y 0x0000000001bddbfc in trx_start_low(trx_t*, bool) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:1380 breakpoint already hit 3 times 12 breakpoint     keep y 0x0000000001c1e9eb in btr_cur_search_to_nth_level(dict_index_t*, ulint, dtuple_t const*, page_cur_mode_t, ulint, btr_cur_t*, ulint, char const*, ulint, mtr_t*) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/btr/btr0cur.cc:770 breakpoint already hit 13 times 13 breakpoint     keep y 0x0000000001859c85 in binlog_start_trans_and_stmt(THD*, Log_event*) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:9737 breakpoint already hit 1 time 14 breakpoint     keep y 0x0000000001845822 in binlog_cache_data::write_event(THD*, Log_event*) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:1114 breakpoint already hit 3 times 15 breakpoint     keep y 0x000000000153a2a3 in THD::enter_stage(PSI_stage_info const*, PSI_stage_info*, char const*, char const*, unsigned int)
                                              at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_class.cc:732 breakpoint already hit 8 times 17 breakpoint     keep y 0x0000000001be195a in trx_prepare(trx_t*) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2947 breakpoint already hit 3 times 19 breakpoint     keep y 0x0000000000f63801 in ha_commit_trans(THD*, bool, bool) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1684 breakpoint already hit 21 times 21 breakpoint     keep y 0x0000000001846901 in binlog_prepare(handlerton*, THD*, bool) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:1578 breakpoint already hit 3 times 24 breakpoint     keep y 0x00000000019c2c64 in innobase_xa_prepare(handlerton*, THD*, bool)
                                              at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:17458 breakpoint already hit 2 times 25 breakpoint     keep y 0x00000000019a9788 in innobase_commit(handlerton*, THD*, bool)
                                              at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:4652 breakpoint already hit 2 times 26 breakpoint     keep y 0x0000000001846442 in binlog_cache_data::flush(THD*, my_off_t*, bool*) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:1408 breakpoint already hit 2 times 27 breakpoint     keep y 0x0000000001857c19 in MYSQL_BIN_LOG::sync_binlog_file(bool) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8802 breakpoint already hit 1 time 28 breakpoint     keep y 0x0000000001bdf2f5 in trx_commit_in_memory(trx_t*, mtr_t const*, bool)
                                              at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:1973

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