Hi Andrei,
On Thursday 22 November 2007 15:39:07, Andrei Elkin wrote:
>Alexey, hello.
>
>> Below is the list of changes that have just been committed into a local
>> 5.1 repository of kaa. When kaa does a push these changes will
>> be propagated to the main repository and, within 24 hours after the
>> push, to the public repository.
>> For information on how to access the public repository
>> see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html
>>
>> ChangeSet@stripped, 2007-11-14 14:42:40+03:00, kaa@polly.(none) +1 -0
>> Fix for bug #29976: Excessive Slave I/O errors in replication tests
>>
>> Problem:
>>
>> The "Slave I/O thread couldn't register on master" error sporadically
>> occurred in replication tests because the slave I/O thread got
>> killed by STOP SLAVE before or while registering on master.
>>
>>
>> Fixed by checking the state of the I/O thread, and issueing
>> the error only if it was not explicitely killed by a user.
>
>I think that's a sound idea. If we know why the IO thread can not
>connect we should not issue an error. The error is for a case we
>don't know why.
>
>What I'd like for you to do is to extend it to cover related issues.
>Before the IO thread gains ON status it makes several client-api
>calls. One your patch is fixing and others are done just before
>register_slave_on_master() in get_master_version_and_clock().
>So let's not panic spewing error messages whenever a killed io fails
>to query the master.
>
Done in the new patch. In fact, there is only one place in
get_master_version_and_clock() where killing the I/O slave could lead to a
warning. All other ones simply ignore any errors (of course, that would be
just caught later in register_slave_on_master()).
>> @@ -2170,11 +2171,15 @@ connected:
>> thd->proc_info = "Registering slave on master";
>> if (register_slave_on_master(mysql, mi, &suppress_warnings))
>> {
>> - sql_print_error("Slave I/O thread couldn't register on master");
>> - if (check_io_slave_killed(thd, mi, "Slave I/O thread killed while \
>> -registering slave on master") ||
>> - try_to_reconnect(thd, mysql, mi, &retry_count,
>> suppress_warnings, -
>> reconnect_messages[SLAVE_RECON_ACT_REG])) + if
>> (!check_io_slave_killed(thd, mi, "Slave I/O thread killed " +
>> "while registering slave on master")) + {
>>
>> + sql_print_error("Slave I/O thread couldn't register on
>> master");
>
>I think we are better to remove this like as there is already
>mi->report(ERROR_LEVEL,...) in register_slave_on_master().
>
Not when mysql_errno() == ER_NET_READ_INTERRUPTED. In such case, we don't
print any error about failing COM_REGISTER_SLAVE, but do print "Slave I/O
thread couldn't register on master" (and then try to reconnect).
That was the old behavior, I just did not see any point in changing it.
Best regards,
--
Alexey Kopytov, Software Developer
MySQL AB, www.mysql.com
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