Question

我在mysql数据库中运行了两个事务，这两个事务似乎都没有取得任何进展。两者都持有一些锁，但据我所知它们不会发生冲突。两个事务都处于“ACTIVE”状态（如果被另一个阻塞，我会预期其中一个处于等待状态）。

我在下面附上了innodb状态输出的“TRANSACTIONS”和“ROW OPERATIONS”部分（包括锁定监视器信息）。

任何人都可以告诉我为什么这些交易会相互影响吗？

我没有一种简单的方法来重现这一点，因为查询是由EJB应用程序发出的，所以我现在试图通常了解这类问题通常会产生什么。

=====================================
100823 16:04:53 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 1 seconds
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 25808, signal count 25608
Mutex spin waits 0, rounds 108338, OS waits 1400
RW-shared spins 18372, OS waits 17512; RW-excl spins 7055, OS waits 6782
------------
TRANSACTIONS
------------
Trx id counter 0 39456296
Purge done for trx's n:o < 0 39455079 undo n:o < 0 0
History list length 2
Total number of lock structs in row lock hash table 3
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 0 39456295, not started, process no 4183, OS thread id 140415939369296
MySQL thread id 21, query id 90163 localhost 127.0.0.1 root
---TRANSACTION 0 0, not started, process no 4183, OS thread id 140415938767184
MySQL thread id 15, query id 89364 cl1010wo2431.inter.rsag.site 172.27.10.38 root
---TRANSACTION 0 0, not started, process no 4183, OS thread id 140415939168592
MySQL thread id 8, query id 90177 localhost root
---TRANSACTION 0 39456204, ACTIVE 94 sec, process no 4183, OS thread id 140415938967888
3 lock struct(s), heap size 368, undo log entries 1
MySQL thread id 23, query id 89811 localhost 127.0.0.1 root
Trx read view will not see trx with id >= 0 39456205, sees < 0 39454738
TABLE LOCK table `server_database/error_data` trx id 0 39456204 lock mode IX
TABLE LOCK table `server_database/error_status` trx id 0 39456204 lock mode IS
RECORD LOCKS space id 2754 page no 3 n bits 72 index `PRIMARY` of table `server_database/error_status` trx id 0 39456204 lock mode S locks rec but not gap
Record lock, heap no 6 PHYSICAL RECORD: n_fields 4; compact format; info bits 0
 0: len 3; hex 800001; asc    ;; 1: len 6; hex 000000d7287f; asc     ( ;; 2: len 7; hex 00000030c816ce; asc    0   ;; 3: len 9; hex 7374617475734e6577; asc statusNew;;
Aug 23 16:04:53 sv1010vm0007 mysqld[4184]:
---TRANSACTION 0 39454738, ACTIVE 1594 sec, process no 4183, OS thread id 140416557721936
6 lock struct(s), heap size 1216, undo log entries 5
MySQL thread id 24, query id 83802 localhost 127.0.0.1 root
Trx read view will not see trx with id >= 0 39454739, sees < 0 39454739
TABLE LOCK table `server_database/error_data` trx id 0 39454738 lock mode IX
TABLE LOCK table `server_database/error_status` trx id 0 39454738 lock mode IS
RECORD LOCKS space id 2754 page no 3 n bits 72 index `PRIMARY` of table `server_database/error_status` trx id 0 39454738 lock mode S locks rec but not gap
Record lock, heap no 6 PHYSICAL RECORD: n_fields 4; compact format; info bits 0
 0: len 3; hex 800001; asc    ;; 1: len 6; hex 000000d7287f; asc     ( ;; 2: len 7; hex 00000030c816ce; asc    0   ;; 3: len 9; hex 7374617475734e6577; asc statusNew;;
Aug 23 16:04:53 sv1010vm0007 mysqld[4184]:
TABLE LOCK table `server_database/wtu_counter_daily` trx id 0 39454738 lock mode IX
TABLE LOCK table `server_database/wtu` trx id 0 39454738 lock mode IS
RECORD LOCKS space id 4349 page no 3 n bits 128 index `PRIMARY` of table `server_database/wtu` trx id 0 39454738 lock mode S locks rec but not gap
Record lock, heap no 62 PHYSICAL RECORD: n_fields 32; compact format; info bits 0
 0: len 3; hex 802715; asc  ' ;; 1: len 6; hex 00000258fa7b; asc    X {;; 2: len 7; hex 000000003401e8; asc     4  ;; 3: SQL NULL; 4: len 3; hex 800005; asc    ;; 5: len 12; hex 31302e37372e33322e313830; asc 10.77.32.180;; 6: len 4; hex 00000040; asc    @;; 7: SQL NULL; 8: SQL NULL; 9: SQL NULL; 10: len 3; hex 8004d2; asc    ;; 11: len 1; hex 37; asc 7;; 12: len 0; hex ; asc ;; 13: len 1; hex 80; asc  ;; 14: len 1; hex 80; asc  ;; 15: SQL NULL; 16: SQL NULL; 17: len 1; hex 35; asc 5;; 18: SQL NULL; 19: len 12; hex 77656273746172742e6a6e6c; asc webstart.jnl;; 20: SQL NULL; 21: len 1; hex 80; asc  ;; 22: len 1; hex 81; asc  ;; 23: len 1; hex 81; asc  ;; 24: len 1; hex 80; asc  ;; 25: len 2; hex 8000; asc   ;; 26: len 13; hex 3139322e3136382e302e313830; asc 192.168.0.180;; 27: len 1; hex 81; asc  ;; 28: SQL NULL; 29: len 4; hex 80000000; asc     ;; 30: len 1; hex 81; asc  ;; 31: SQL NULL;

--------------
ROW OPERATIONS
--------------
0 queries inside InnoDB, 0 queries in queue
3 read views open inside InnoDB
Main thread process no. 4183, id 140415947962704, state: waiting for server activity
Number of rows inserted 64, updated 450, deleted 0, read 89832081
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================

Answer 1

是的，在mysql中

示例： - 如果在mysql服务器上运行4命令

然后当第二个命令进入服务器然后他等待第一个和第三个命令的响应等待第二个命令响应然后服务器接受它们。

如果上一个命令的响应没有从服务器发出，那么他就不能接受下一个命令。

然后你需要确保一次只运行一个命令或事务。

您还可以在连接字符串中增加命令执行的超时时间。

两个交易似乎相互阻止，但没有一个等待

1 个答案: