mysql deadlock with foreign key - mysql

Question

DDL(removed some irrelevant columns info)
Table: config_version
Create Table: CREATE TABLE `config_version` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`config_id` bigint(20) DEFAULT NULL,
PRIMARY KEY (`id`),
KEY `fk_config_version_config_1` (`config_id`),
CONSTRAINT `fk_config_version_config_1` FOREIGN KEY (`config_id`) REFERENCES `config` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=85532 DEFAULT CHARSET=utf8 COLLATE=utf8_bin ROW_FORMAT=COMPACT
Table: config
Create Table: CREATE TABLE `config` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`id`),
UNIQUE KEY `unique_config_name_namespace_id` (`name`,`namespace_id`),
KEY `fk_config_namespace_1` (`namespace_id`),
CONSTRAINT `fk_config_namespace_1` FOREIGN KEY (`namespace_id`) REFERENCES `namespace` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1901 DEFAULT CHARSET=utf8 COLLATE=utf8_bin ROW_FORMAT=COMPACT
show engine innodb status;
*** (1) TRANSACTION:
TRANSACTION 125411, ACTIVE 0 sec starting index read
mysql tables in use 1, locked 1
LOCK WAIT 5 lock struct(s), heap size 1136, 2 row lock(s), undo log entries 1
MySQL thread id 7, OS thread handle 123145570861056, query id 4898 localhost 127.0.0.1 root updating
update config set name = 'bts_driver_list_filter_gray_onceagain_list_filter_tw_control_group', description = '?????????????', namespace_id = 4, current_version = 89950, create_time = '2017-11-14 15:54:45', created_by = 'chenchongyu' where id = 982
2017-12-01T04:12:43.711301Z 6 [Note] InnoDB: *** (1) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 672 page no 11 n bits 216 index PRIMARY of table `apollo_config_dev`.`config` trx id 125411 lock_mode X locks rec but not gap waiting
Record lock, heap no 97 PHYSICAL RECORD: n_fields 10; compact format; info bits 0
0: len 8; hex 80000000000003d6; asc ;;
1: len 6; hex 00000001e9da; asc ;;
2: len 7; hex 24000001830584; asc $ ;;
3: len 30; hex 6274735f6472697665725f6c6973745f66696c7465725f677261795f6f6e; asc bts_driver_list_filter_gray_on; (total 66 bytes);
4: len 13; hex 3f3f3f3f3f3f3f3f3f3f3f3f3f; asc ?????????????;;
5: len 11; hex 6368656e63686f6e677975; asc chenchongyu;;
6: len 8; hex 8000000000000004; asc ;;
7: len 8; hex 8000000000015f56; asc _V;;
8: len 5; hex 999e1cfdad; asc ;;
9: len 1; hex 01; asc ;;
2017-12-01T04:12:43.712251Z 6 [Note] InnoDB: *** (2) TRANSACTION:
TRANSACTION 125408, ACTIVE 0 sec starting index read
mysql tables in use 1, locked 1
5 lock struct(s), heap size 1136, 2 row lock(s), undo log entries 1
MySQL thread id 6, OS thread handle 123145570582528, query id 4904 localhost 127.0.0.1 root updating
update config set name = 'bts_driver_list_filter_gray_onceagain_list_filter_tw_control_group', description = '?????????????', namespace_id = 4, current_version = 89947, create_time = '2017-11-14 15:54:45', created_by = 'chenchongyu' where id = 982
2017-12-01T04:12:43.712308Z 6 [Note] InnoDB: *** (2) HOLDS THE LOCK(S):
RECORD LOCKS space id 672 page no 11 n bits 216 index PRIMARY of table `apollo_config_dev`.`config` trx id 125408 lock mode S locks rec but not gap
Record lock, heap no 97 PHYSICAL RECORD: n_fields 10; compact format; info bits 0
0: len 8; hex 80000000000003d6; asc ;;
1: len 6; hex 00000001e9da; asc ;;
2: len 7; hex 24000001830584; asc $ ;;
3: len 30; hex 6274735f6472697665725f6c6973745f66696c7465725f677261795f6f6e; asc bts_driver_list_filter_gray_on; (total 66 bytes);
4: len 13; hex 3f3f3f3f3f3f3f3f3f3f3f3f3f; asc ?????????????;;
5: len 11; hex 6368656e63686f6e677975; asc chenchongyu;;
6: len 8; hex 8000000000000004; asc ;;
7: len 8; hex 8000000000015f56; asc _V;;
8: len 5; hex 999e1cfdad; asc ;;
9: len 1; hex 01; asc ;;
2017-12-01T04:12:43.713122Z 6 [Note] InnoDB: *** (2) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 672 page no 11 n bits 216 index PRIMARY of table `apollo_config_dev`.`config` trx id 125408 lock_mode X locks rec but not gap waiting
Record lock, heap no 97 PHYSICAL RECORD: n_fields 10; compact format; info bits 0
0: len 8; hex 80000000000003d6; asc ;;
1: len 6; hex 00000001e9da; asc ;;
2: len 7; hex 24000001830584; asc $ ;;
3: len 30; hex 6274735f6472697665725f6c6973745f66696c7465725f677261795f6f6e; asc bts_driver_list_filter_gray_on; (total 66 bytes);
4: len 13; hex 3f3f3f3f3f3f3f3f3f3f3f3f3f; asc ?????????????;;
5: len 11; hex 6368656e63686f6e677975; asc chenchongyu;;
6: len 8; hex 8000000000000004; asc ;;
7: len 8; hex 8000000000015f56; asc _V;;
8: len 5; hex 999e1cfdad; asc ;;
9: len 1; hex 01; asc ;;
2017-12-01T04:12:43.714133Z 6 [Note] InnoDB: *** WE ROLL BACK TRANSACTION (2)
简化业务流程代码(code)
#Transaction
public void service(){
Config config = configMapper.selectByPrimaryKey(configId)
ConfigVersion configVersion = toConfigVersion(config, configDTO)
configVersionMapper.insert(configVersion)
config.setCurrentVersion(configVersion.id)
config.setDescription(configDTO.description)
configMapper.updateByPrimaryKey(config)
wait for service C http response
}
sql of the code
insert into config_version (config_id, name, create_time, namespace_id, type, status,base_version_id, value, created_by, enable_from, description)
values
( #{configId,jdbcType=BIGINT},
#{name,jdbcType=VARCHAR}, now(),
#{namespaceId,jdbcType=BIGINT}, #{type,jdbcType=TINYINT},
#{status,jdbcType=TINYINT},
#{baseVersionId,jdbcType=BIGINT}, #{value,jdbcType=LONGVARCHAR}, #{createdBy,jdbcType=VARCHAR},
#{enableFrom,jdbcType=TIMESTAMP},#{description,jdbcType=VARCHAR})
update config set
name = #{name,jdbcType=VARCHAR},
description = #{description,jdbcType=VARCHAR},
namespace_id = #{namespaceId,jdbcType=BIGINT},
current_version = #{currentVersion,jdbcType=BIGINT},
create_time = #{createTime,jdbcType=TIMESTAMP},
created_by = #{createdBy,jdbcType=VARCHAR}
where id = #{id,jdbcType=BIGINT}
业务场景(service invoke order)
服务A 调用服务B 更新 config version,服务B 将更新内容持久化到mysql 以后会调用服务C,等待服务C返回以后，服务B再返回给服务A
如果服务A 一定时间内没有接受到服务B返回,那么服务A 会重试，重新向服务A 发起一个请求
(service A -> A, service B -> B, service C ->C;
A invoke B, to update config_version,B persist to mysql, and then invoke C,after C returned, B return to A.
A will retry if B did not return;
)
解决办法(solution)
去掉config_version 对config的外键依赖(remove the foreign key)
CONSTRAINT `fk_config_version_config_1` FOREIGN KEY (`config_id`) REFERENCES `config` (`id`)
Question
但是没明白mysql insert 和update 时需要获取什么锁，所以没明白这里产生死锁的原因。
(the reason why deadlock happened, which kind of lock get in a tx)
软件版本信息(mysql info)
sql
mysql 版本信息
mysql: stable 5.7.20