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十五:MySQL层事务提交流程简析(笔记)

欢迎关注我的《深入理解MySQL主从原理 32讲 》,如下:

如果图片不能显示可查看下面链接:
https://www.jianshu.com/p/d636215d767f

部分栈帧:

2、prepare栈帧

  (gdb) bt  #0  binlog_prepare (hton=0x346f260, thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:1578  #1  0x0000000000f64e80 in ha_prepare_low (thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:2348  #2  0x0000000001856176 in MYSQL_BIN_LOG::prepare (this=0x2dffe80, thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8165  #3  0x0000000000f63d1f in ha_commit_trans (thd=0x7fff2c000b70, all=false, ignore_global_read_lock=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1803  #4  0x00000000016b3d7d in trans_commit_stmt (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/transaction.cc:458  #5  0x00000000015ac64f in mysql_execute_command (thd=0x7fff2c000b70, first_level=true) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5239  #6  0x00000000015adcae in mysql_parse (thd=0x7fff2c000b70, parser_state=0x7ffff035b600) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5836  #7  0x00000000015a1b6d in dispatch_command (thd=0x7fff2c000b70, com_data=0x7ffff035bd70, command=COM_QUERY)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1447  #8  0x00000000015a099e in do_command (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1010  #9  0x00000000016e28f0 in handle_connection (arg=0x384a5d0) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/conn_handler/connection_handler_per_thread.cc:312  #10 0x0000000001d7a514 in pfs_spawn_thread (arg=0x3848260) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/perfschema/pfs.cc:2188  #11 0x0000003f74807aa1 in start_thread () from /lib64/libpthread.so.0  #12 0x0000003f740e8bcd in clone () from /lib64/libc.so.6  (gdb) b innobase_trx_init  Breakpoint 7 at 0x19a5fdb: file /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc, line 2753.  (gdb) c  Continuing.  

trx_prepare_low

  Breakpoint 7, innobase_trx_init (thd=0x7fff2c000b70, trx=0x7ffff2f2db00) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:2753  2753            DBUG_ENTER("innobase_trx_init");  (gdb) bt   #0  innobase_trx_init (thd=0x7fff2c000b70, trx=0x7ffff2f2db00) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:2753  #1  0x00000000019a6291 in check_trx_exists (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:2816  #2  0x00000000019c2b90 in innobase_xa_prepare (hton=0x2e9cdd0, thd=0x7fff2c000b70, prepare_trx=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:17458  #3  0x0000000000f64e80 in ha_prepare_low (thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:2348  #4  0x0000000001856176 in MYSQL_BIN_LOG::prepare (this=0x2dffe80, thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8165  #5  0x0000000000f63d1f in ha_commit_trans (thd=0x7fff2c000b70, all=false, ignore_global_read_lock=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1803  #6  0x00000000016b3d7d in trans_commit_stmt (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/transaction.cc:458  #7  0x00000000015ac64f in mysql_execute_command (thd=0x7fff2c000b70, first_level=true) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5239  #8  0x00000000015adcae in mysql_parse (thd=0x7fff2c000b70, parser_state=0x7ffff035b600) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5836  #9  0x00000000015a1b6d in dispatch_command (thd=0x7fff2c000b70, com_data=0x7ffff035bd70, command=COM_QUERY)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1447  #10 0x00000000015a099e in do_command (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1010  #11 0x00000000016e28f0 in handle_connection (arg=0x384a5d0) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/conn_handler/connection_handler_per_thread.cc:312  #12 0x0000000001d7a514 in pfs_spawn_thread (arg=0x3848260) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/perfschema/pfs.cc:2188  #13 0x0000003f74807aa1 in start_thread () from /lib64/libpthread.so.0  #14 0x0000003f740e8bcd in clone () from /lib64/libc.so.6  (gdb)  

3、flush 之前写redo 栈帧
1145 bool write_header = new_data_offset == 0;

  (gdb) bt  #0  log_group_write_buf (group=0x33ef9f8, buf=0x7fffa5b38000 "2002030025302", len=1024, pad_len=0, start_lsn=562123776, new_data_offset=465)      at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/log/log0log.cc:1145  #1  0x0000000001a50dd5 in log_write_up_to (lsn=562124558, flush_to_disk=true) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/log/log0log.cc:1493  #2  0x0000000001a50ec7 in log_buffer_flush_to_disk (sync=true) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/log/log0log.cc:1524  #3  0x00000000019a9077 in innobase_flush_logs (hton=0x2e9cdd0, binlog_group_flush=true)      at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:4407  #4  0x0000000000f65893 in flush_handlerton (thd=0x0, plugin=0x7ffff03588e8, arg=0x7ffff0358944) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:2606  #5  0x00000000015d76ee in plugin_foreach_with_mask (thd=0x0, func=0xf65835 <flush_handlerton(THD*, plugin_ref, void*)>, type=1, state_mask=4294967287,       arg=0x7ffff0358944) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_plugin.cc:2318  #6  0x0000000000f658ef in ha_flush_logs (db_type=0x0, binlog_group_flush=true) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:2617  #7  0x000000000185725d in MYSQL_BIN_LOG::process_flush_stage_queue (this=0x2dffe80, total_bytes_var=0x7ffff0358a88, rotate_var=0x7ffff0358a87,       out_queue_var=0x7ffff0358a78) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8541  #8  0x00000000018588bf in MYSQL_BIN_LOG::ordered_commit (this=0x2dffe80, thd=0x7fff2c000b70, all=false, skip_commit=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:9189  #9  0x0000000001856f2c in MYSQL_BIN_LOG::commit (this=0x2dffe80, thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8440  #10 0x0000000000f63df8 in ha_commit_trans (thd=0x7fff2c000b70, all=false, ignore_global_read_lock=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1818  #11 0x00000000016b3d7d in trans_commit_stmt (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/transaction.cc:458  #12 0x00000000015ac64f in mysql_execute_command (thd=0x7fff2c000b70, first_level=true) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5239  #13 0x00000000015adcae in mysql_parse (thd=0x7fff2c000b70, parser_state=0x7ffff035b600) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5836  #14 0x00000000015a1b6d in dispatch_command (thd=0x7fff2c000b70, com_data=0x7ffff035bd70, command=COM_QUERY)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1447  #15 0x00000000015a099e in do_command (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1010  #16 0x00000000016e28f0 in handle_connection (arg=0x68e1060) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/conn_handler/connection_handler_per_thread.cc:312  #17 0x0000000001d7a514 in pfs_spawn_thread (arg=0x3848660) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/perfschema/pfs.cc:2188  #18 0x0000003f74807aa1 in start_thread () from /lib64/libpthread.so.0  #19 0x0000003f740e8bcd in clone () from /lib64/libc.so.6  

4、order commit innodb层commit栈帧

    Breakpoint 2, trx_purge_add_update_undo_to_history (trx=0x7ffff2f2e068, undo_ptr=0x7ffff2f2e488, undo_page=0x7fffb0244000 "E373332r", update_rseg_history_len=true,       n_added_logs=1, mtr=0x7ffff03582f0) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0purge.cc:332  332             undo = undo_ptr->update_undo;  (gdb) bt  #0  trx_purge_add_update_undo_to_history (trx=0x7ffff2f2e068, undo_ptr=0x7ffff2f2e488, undo_page=0x7fffb0244000 "E373332r", update_rseg_history_len=true,       n_added_logs=1, mtr=0x7ffff03582f0) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0purge.cc:332  #1  0x0000000001bef543 in trx_undo_update_cleanup (trx=0x7ffff2f2e068, undo_ptr=0x7ffff2f2e488, undo_page=0x7fffb0244000 "E373332r", update_rseg_history_len=true,       n_added_logs=1, mtr=0x7ffff03582f0) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0undo.cc:1962  #2  0x0000000001bddf57 in trx_write_serialisation_history (trx=0x7ffff2f2e068, mtr=0x7ffff03582f0)      at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:1698  #3  0x0000000001bdf45d in trx_commit_low (trx=0x7ffff2f2e068, mtr=0x7ffff03582f0) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2204  #4  0x0000000001bdf5d2 in trx_commit (trx=0x7ffff2f2e068) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2274  #5  0x0000000001bdff38 in trx_commit_for_mysql (trx=0x7ffff2f2e068) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2550  #6  0x00000000019a9101 in innobase_commit_low (trx=0x7ffff2f2e068) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:4451  #7  0x00000000019a99e7 in innobase_commit (hton=0x2e9cdd0, thd=0x7fff2c000b70, commit_trx=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:4740  #8  0x0000000000f64104 in ha_commit_low (thd=0x7fff2c000b70, all=false, run_after_commit=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1923  #9  0x000000000185764b in MYSQL_BIN_LOG::process_commit_stage_queue (this=0x2dffe80, thd=0x7fff2c000b70, first=0x7fff2c000b70)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8647  #10 0x0000000001858e7d in MYSQL_BIN_LOG::ordered_commit (this=0x2dffe80, thd=0x7fff2c000b70, all=false, skip_commit=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:9318  #11 0x0000000001856f2c in MYSQL_BIN_LOG::commit (this=0x2dffe80, thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8440  #12 0x0000000000f63df8 in ha_commit_trans (thd=0x7fff2c000b70, all=false, ignore_global_read_lock=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1818  #13 0x00000000016b3d7d in trans_commit_stmt (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/transaction.cc:458  #14 0x00000000015ac64f in mysql_execute_command (thd=0x7fff2c000b70, first_level=true) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5239  #15 0x00000000015adcae in mysql_parse (thd=0x7fff2c000b70, parser_state=0x7ffff035b600) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5836  #16 0x00000000015a1b6d in dispatch_command (thd=0x7fff2c000b70, com_data=0x7ffff035bd70, command=COM_QUERY)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1447  #17 0x00000000015a099e in do_command (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1010  #18 0x00000000016e28f0 in handle_connection (arg=0x68e11d0) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/conn_handler/connection_handler_per_thread.cc:312  #19 0x0000000001d7a514 in pfs_spawn_thread (arg=0x38484d0) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/perfschema/pfs.cc:2188  #20 0x0000003f74807aa1 in start_thread () from /lib64/libpthread.so.0  #21 0x0000003f740e8bcd in clone () from /lib64/libc.so.6  (gdb) c  Continuing.  Breakpoint 8, trx_commit_in_memory (trx=0x7ffff2f2e068, mtr=0x7ffff03582f0, serialised=true)      at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:1972  1972            trx->must_flush_log_later = false;  (gdb) bt  #0  trx_commit_in_memory (trx=0x7ffff2f2e068, mtr=0x7ffff03582f0, serialised=true) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:1972  #1  0x0000000001bdf52a in trx_commit_low (trx=0x7ffff2f2e068, mtr=0x7ffff03582f0) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2250  #2  0x0000000001bdf5d2 in trx_commit (trx=0x7ffff2f2e068) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2274  #3  0x0000000001bdff38 in trx_commit_for_mysql (trx=0x7ffff2f2e068) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2550  #4  0x00000000019a9101 in innobase_commit_low (trx=0x7ffff2f2e068) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:4451  #5  0x00000000019a99e7 in innobase_commit (hton=0x2e9cdd0, thd=0x7fff2c000b70, commit_trx=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:4740  #6  0x0000000000f64104 in ha_commit_low (thd=0x7fff2c000b70, all=false, run_after_commit=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1923  #7  0x000000000185764b in MYSQL_BIN_LOG::process_commit_stage_queue (this=0x2dffe80, thd=0x7fff2c000b70, first=0x7fff2c000b70)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8647  #8  0x0000000001858e7d in MYSQL_BIN_LOG::ordered_commit (this=0x2dffe80, thd=0x7fff2c000b70, all=false, skip_commit=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:9318  #9  0x0000000001856f2c in MYSQL_BIN_LOG::commit (this=0x2dffe80, thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8440  #10 0x0000000000f63df8 in ha_commit_trans (thd=0x7fff2c000b70, all=false, ignore_global_read_lock=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1818  #11 0x00000000016b3d7d in trans_commit_stmt (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/transaction.cc:458  #12 0x00000000015ac64f in mysql_execute_command (thd=0x7fff2c000b70, first_level=true) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5239  #13 0x00000000015adcae in mysql_parse (thd=0x7fff2c000b70, parser_state=0x7ffff035b600) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5836  #14 0x00000000015a1b6d in dispatch_command (thd=0x7fff2c000b70, com_data=0x7ffff035bd70, command=COM_QUERY)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1447  #15 0x00000000015a099e in do_command (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1010  #16 0x00000000016e28f0 in handle_connection (arg=0x68e11d0) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/conn_handler/connection_handler_per_thread.cc:312  #17 0x0000000001d7a514 in pfs_spawn_thread (arg=0x38484d0) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/perfschema/pfs.cc:2188  #18 0x0000003f74807aa1 in start_thread () from /lib64/libpthread.so.0  #19 0x0000003f740e8bcd in clone () from /lib64/libc.so.6  (gdb) c  Continuing.  Breakpoint 3, trx_commit_complete_for_mysql (trx=0x7ffff2f2e068) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2570  2570            if (trx->id != 0  (gdb) bt  #0  trx_commit_complete_for_mysql (trx=0x7ffff2f2e068) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/trx/trx0trx.cc:2570  #1  0x00000000019a9aab in innobase_commit (hton=0x2e9cdd0, thd=0x7fff2c000b70, commit_trx=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/storage/innobase/handler/ha_innodb.cc:4762  #2  0x0000000000f64104 in ha_commit_low (thd=0x7fff2c000b70, all=false, run_after_commit=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1923  #3  0x000000000185764b in MYSQL_BIN_LOG::process_commit_stage_queue (this=0x2dffe80, thd=0x7fff2c000b70, first=0x7fff2c000b70)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8647  #4  0x0000000001858e7d in MYSQL_BIN_LOG::ordered_commit (this=0x2dffe80, thd=0x7fff2c000b70, all=false, skip_commit=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:9318  #5  0x0000000001856f2c in MYSQL_BIN_LOG::commit (this=0x2dffe80, thd=0x7fff2c000b70, all=false) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/binlog.cc:8440  #6  0x0000000000f63df8 in ha_commit_trans (thd=0x7fff2c000b70, all=false, ignore_global_read_lock=false)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/handler.cc:1818  #7  0x00000000016b3d7d in trans_commit_stmt (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/transaction.cc:458  #8  0x00000000015ac64f in mysql_execute_command (thd=0x7fff2c000b70, first_level=true) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5239  #9  0x00000000015adcae in mysql_parse (thd=0x7fff2c000b70, parser_state=0x7ffff035b600) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:5836  #10 0x00000000015a1b6d in dispatch_command (thd=0x7fff2c000b70, com_data=0x7ffff035bd70, command=COM_QUERY)      at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1447  #11 0x00000000015a099e in do_command (thd=0x7fff2c000b70) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/sql_parse.cc:1010  #12 0x00000000016e28f0 in handle_connection (arg=0x68e11d0) at /root/mysql5.7.14/percona-server-5.7.14-7/sql/conn_handler/connection_handler_per_thread.cc:312  #13 0x0000000001d7a514 in pfs_spawn_thread (arg=0x38484d0) at /root/mysql5.7.14/percona-server-5.7.14-7/storage/perfschema/pfs.cc:2188  #14 0x0000003f74807aa1 in start_thread () from /lib64/libpthread.so.0  #15 0x0000003f740e8bcd in clone () from /lib64/libc.so.6  

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