#At file:///home/daogangqu/mysql/bzrwork1/bug53167/mysql-next-mr-bugfixing/ based on revid:vvaintroub@stripped
3192 Dao-Gang.Qu@stripped 2010-08-30
Bug #53167 Seconds_Behind_Master is wrong after start slave
When a slave server has an existing relay log and the user issues
START SLAVE, the output from "SHOW SLAVE STATUS" shows a wrong
value for Seconds_Behind_Master until the first event from the relay
log has finished executing. The displayed value for Seconds_Behind_Master
is calculated based on the timestamp of the Format_Description_Log_Event
from master. This can be a very big number if the relay log was created
long ago.
The Timestamp recorded in Format_Description_Log_Event should not be used
when executing the Format_Description_Log_Event on slave. So do not assign
the Timestamp of the Format_Description_Log_Event to last_master_timestamp.
Then the peak value will disappear.
@ mysql-test/suite/rpl/t/rpl_delayed_slave.test
Upadted to test the patch of Bug #53167.
@ sql/binlog.cc
Added code to set LOG_EVENT_RELAY_LOG_F flag for relay log's FD
@ sql/rpl_slave.cc
Added code to update the last_master_timestamp at the end of a
transaction(to non-transation, treat every statement as a transaction
as it is enclosed with 'BEGIN' and 'COMMIT' in binary log) for
making the value of Seconds_Behind_Master more reasonable.
modified:
mysql-test/suite/rpl/t/rpl_delayed_slave.test
sql/binlog.cc
sql/rpl_slave.cc
=== modified file 'mysql-test/suite/rpl/t/rpl_delayed_slave.test'
--- a/mysql-test/suite/rpl/t/rpl_delayed_slave.test 2010-06-21 12:32:29 +0000
+++ b/mysql-test/suite/rpl/t/rpl_delayed_slave.test 2010-08-30 10:59:23 +0000
@@ -183,15 +183,16 @@ INSERT INTO t1(a) VALUES (delay_on_slave
--echo # sleep 1*T
--sleep $time1
+let $bug_53167_is_fixed= 1;
if ($bug_53167_is_fixed) {
-
---let $seconds_behind_master= query_get_value(SHOW SLAVE STATUS, Seconds_Behind_Master, 1)
-if (`SELECT $seconds_behind_master <= 0 OR $seconds_behind_master >= $time2`) {
- --echo Seconds_Behind_Master was $seconds_behind_master. Expected that 0 < Seconds_Behind_Master < SQL_Delay = $time2
- --source include/show_rpl_debug_info.inc
- --die Seconds_Behind_Master was wrong
-}
-
+ --let $seconds_behind_master= query_get_value(SHOW SLAVE STATUS, Seconds_Behind_Master, 1)
+ # The value of Seconds_Behind_Master will be zero
+ # before the first non-FD event is executed.
+ if (`SELECT $seconds_behind_master < 0 OR $seconds_behind_master >= $time2`) {
+ --echo Seconds_Behind_Master was $seconds_behind_master. Expected that 0 =< Seconds_Behind_Master < SQL_Delay = $time2
+ --source include/show_rpl_debug_info.inc
+ --die Seconds_Behind_Master was wrong
+ }
}
--echo # sleep 1*T
=== modified file 'sql/binlog.cc'
--- a/sql/binlog.cc 2010-07-29 12:32:36 +0000
+++ b/sql/binlog.cc 2010-08-30 10:59:23 +0000
@@ -1597,6 +1597,9 @@ bool MYSQL_BIN_LOG::open(const char *log
if (!s.is_valid())
goto err;
s.dont_set_created= null_created_arg;
+ /* Set LOG_EVENT_RELAY_LOG_F flag for relay log's FD */
+ if (is_relay_log)
+ s.flags|= LOG_EVENT_RELAY_LOG_F;
if (s.write(&log_file))
goto err;
bytes_written+= s.data_written;
=== modified file 'sql/rpl_slave.cc'
--- a/sql/rpl_slave.cc 2010-08-04 10:34:01 +0000
+++ b/sql/rpl_slave.cc 2010-08-30 10:59:23 +0000
@@ -2679,16 +2679,17 @@ static int exec_relay_log_event(THD* thd
{
int exec_res;
- /*
+ /*
Even if we don't execute this event, we keep the master timestamp,
so that seconds behind master shows correct delta (there are events
that are not replayed, so we keep falling behind).
If it is an artificial event, or a relay log event (IO thread generated
- event) or ev->when is set to 0, we don't update the
+ event) or ev->when is set to 0, or a FD from master, we don't update the
last_master_timestamp.
- */
- if (!(ev->is_artificial_event() || ev->is_relay_log_event() || (ev->when == 0)))
+ */
+ if (!(ev->is_artificial_event() || ev->is_relay_log_event() ||
+ (ev->when == 0) || ev->get_type_code() == FORMAT_DESCRIPTION_EVENT))
{
rli->last_master_timestamp= ev->when + (time_t) ev->exec_time;
DBUG_ASSERT(rli->last_master_timestamp >= 0);
Attachment: [text/bzr-bundle] bzr/dao-gang.qu@sun.com-20100830105923-9mpmvzrwtaumssrv.bundle
