Bug #25713 contents in file relay-log sometimes error
Submitted: 19 Jan 2007 2:09 Modified: 30 Jan 2007 6:53
Reporter: mingfei hua Email Updates:
Status: Verified Impact on me:
None 
Category:MySQL Server: Replication Severity:S1 (Critical)
Version:5.0.24 OS:Mac OS X (Mac OS X)
Assigned to: Assigned Account CPU Architecture:Any
Triage: Triaged: D3 (Medium)

[19 Jan 2007 2:09] mingfei hua
Description:
Two mysql server ,server A is master,server B is slave, write a script to insert
data to server A,then the data will be replicated to server B,in this time ,I check the file relay-log.info.the file always like mysql document discribed as
list below:

./localhost-relay-bin.000002
232
binlog.000006
263443365

but some occations ,the file content is like :

./localhost-relay-bin.000002
232
binlog.000006
263
2324

The value of line 4 "263" is not I expected,it should be larger then "263443365",otherwise,what's the meaning of line 5 "2324".

How to repeat:
Install two mysql server ,server A is replication master,server B is replication slave, 
write a procedure like "BEGIN
   DECLARE id INT;
   set id=0;
   while id<1000000 do
      INSERT INTO test.tt VALUES (id);
      set id=id+1;
   end while;
END " to insert data to server A ,at the same time ,execute script like "
while [ 1 ]
do
cat /root/relay-log.info.5|awk 'begin{line=0}{line++}{if(line==4)print;if(line==5) print}'
sleep 1
done" to check file relay-log.info in server B. You can see the result is not
what you expected.
[19 Jan 2007 8:41] mingfei hua
I found the result of "show slave status " also is not correct.

"mysql> show slave status \G;
*************************** 1. row ***************************
             Slave_IO_State: Waiting for master to send event
                Master_Host: 10.0.1.233
                Master_User: repl
                Master_Port: 3306
              Connect_Retry: 60
            Master_Log_File: binlog.000008
        Read_Master_Log_Pos: 286221092
             Relay_Log_File: localhost-relay-bin.000005
              Relay_Log_Pos: 240318226
      Relay_Master_Log_File: binlog.000008
           Slave_IO_Running: Yes
          Slave_SQL_Running: Yes
            Replicate_Do_DB: 
        Replicate_Ignore_DB: wp_core,mysql
         Replicate_Do_Table: 
     Replicate_Ignore_Table: diacare.online_shopping_car,test.test3
    Replicate_Wild_Do_Table: 
Replicate_Wild_Ignore_Table: 
                 Last_Errno: 0
                 Last_Error: 
               Skip_Counter: 0
        Exec_Master_Log_Pos: 240318092
            Relay_Log_Space: 286221226
            Until_Condition: None
             Until_Log_File: 
              Until_Log_Pos: 0
         Master_SSL_Allowed: No
         Master_SSL_CA_File: 
         Master_SSL_CA_Path: 
            Master_SSL_Cert: 
          Master_SSL_Cipher: 
             Master_SSL_Key: 
      Seconds_Behind_Master: 94
1 row in set (0.00 sec)

ERROR: 
No query specified

mysql> show slave status \G;
*************************** 1. row ***************************
             Slave_IO_State: Waiting for master to send event
                Master_Host: 10.0.1.233
                Master_User: repl
                Master_Port: 3306
              Connect_Retry: 60
            Master_Log_File: binlog.000008
        Read_Master_Log_Pos: 286388324
             Relay_Log_File: localhost-relay-bin.000005
              Relay_Log_Pos: 240537847
      Relay_Master_Log_File: binlog.000008
           Slave_IO_Running: Yes
          Slave_SQL_Running: Yes
            Replicate_Do_DB: 
        Replicate_Ignore_DB: wp_core,mysql
         Replicate_Do_Table: 
     Replicate_Ignore_Table: diacare.online_shopping_car,test.test3
    Replicate_Wild_Do_Table: 
Replicate_Wild_Ignore_Table: 
                 Last_Errno: 0
                 Last_Error: 
               Skip_Counter: 0
        Exec_Master_Log_Pos: 129
            Relay_Log_Space: 286388458
            Until_Condition: None
             Until_Log_File: 
              Until_Log_Pos: 0
         Master_SSL_Allowed: No
         Master_SSL_CA_File: 
         Master_SSL_CA_Path: 
            Master_SSL_Cert: 
          Master_SSL_Cipher: 
             Master_SSL_Key: 
      Seconds_Behind_Master: 95
1 row in set (0.00 sec)

ERROR: 
No query specified

mysql> "

the value Exec_Master_Log_Pos sudenly very small
[22 Jan 2007 13:33] Valeriy Kravchuk
Thank you for a problem report. Please, try to repeat with a newer version, 5.0.27 at least, and inform about the results.
[24 Jan 2007 2:54] mingfei hua
I retry in mysql 5.0.27,the result is same.
[29 Jan 2007 10:39] Sveta Smirnova
Please indicate Operation System you use.
[29 Jan 2007 12:10] Sveta Smirnova
Thank you for the report.

Verified as described on Mac OS using last BK sources.
[30 Jan 2007 6:53] mingfei hua
GNU/Linux 2.6.16 x86_64
[30 Jun 2015 23:24] Sveta Smirnova
Still exists in version 5.6.24. See https://bugs.launchpad.net/mysql-server/+bug/1470273