diff options
Diffstat (limited to 'sql')
| -rw-r--r-- | sql/log.cc | 7 | ||||
| -rw-r--r-- | sql/rpl_mi.cc | 1 | ||||
| -rw-r--r-- | sql/rpl_mi.h | 6 | ||||
| -rw-r--r-- | sql/slave.cc | 80 |
4 files changed, 94 insertions, 0 deletions
diff --git a/sql/log.cc b/sql/log.cc index 71975cd83b7..e6d9b6d15cb 100644 --- a/sql/log.cc +++ b/sql/log.cc @@ -7469,6 +7469,13 @@ MYSQL_BIN_LOG::write_transaction_or_stmt(group_commit_entry *entry, } } + DBUG_EXECUTE_IF("inject_error_writing_xid", + { + entry->error_cache= NULL; + entry->commit_errno= 28; + DBUG_RETURN(ER_ERROR_ON_WRITE); + }); + if (entry->end_event->write(&log_file)) { entry->error_cache= NULL; diff --git a/sql/rpl_mi.cc b/sql/rpl_mi.cc index 7764400becb..f2c39ea7f8d 100644 --- a/sql/rpl_mi.cc +++ b/sql/rpl_mi.cc @@ -38,6 +38,7 @@ Master_info::Master_info(LEX_STRING *connection_name_arg, connect_retry(DEFAULT_CONNECT_RETRY), inited(0), abort_slave(0), slave_running(0), slave_run_id(0), sync_counter(0), heartbeat_period(0), received_heartbeats(0), master_id(0), + prev_master_id(0), using_gtid(USE_GTID_NO), events_queued_since_last_gtid(0), gtid_reconnect_event_skip_count(0), gtid_event_seen(false) { diff --git a/sql/rpl_mi.h b/sql/rpl_mi.h index af739b1dad4..ebb1b541728 100644 --- a/sql/rpl_mi.h +++ b/sql/rpl_mi.h @@ -136,6 +136,12 @@ class Master_info : public Slave_reporting_capability DYNAMIC_ARRAY ignore_server_ids; ulong master_id; /* + At reconnect and until the first rotate event is seen, prev_master_id is + the value of master_id during the previous connection, used to detect + silent change of master server during reconnects. + */ + ulong prev_master_id; + /* Which kind of GTID position (if any) is used when connecting to master. Note that you can not change the numeric values of these, they are used diff --git a/sql/slave.cc b/sql/slave.cc index ae3cb86e8be..9422ecc7f22 100644 --- a/sql/slave.cc +++ b/sql/slave.cc @@ -5265,6 +5265,86 @@ static int queue_event(Master_info* mi,const char* buf, ulong event_len) event_len - BINLOG_CHECKSUM_LEN : event_len, mi->rli.relay_log.description_event_for_queue); + if (unlikely(mi->gtid_reconnect_event_skip_count) && + unlikely(!mi->gtid_event_seen) && + rev.is_artificial_event() && + (mi->prev_master_id != mi->master_id || + strcmp(rev.new_log_ident, mi->master_log_name) != 0)) + { + /* + Artificial Rotate_log_event is the first event we receive at the start + of each master binlog file. It gives the name of the new binlog file. + + Normally, we already have this name from the real rotate event at the + end of the previous binlog file (unless we are making a new connection + using GTID). But if the master server restarted/crashed, there is no + rotate event at the end of the prior binlog file, so the name is new. + + We use this fact to handle a special case of master crashing. If the + master crashed while writing the binlog, it might end with a partial + event group lacking the COMMIT/XID event, which must be rolled + back. If the slave IO thread happens to get a disconnect in the middle + of exactly this event group, it will try to reconnect at the same GTID + and skip already fetched events. However, that GTID did not commit on + the master before the crash, so it does not really exist, and the + master will connect the slave at the next following GTID starting in + the next binlog. This could confuse the slave and make it mix the + start of one event group with the end of another. + + But we detect this case here, by noticing the change of binlog name + which detects the missing rotate event at the end of the previous + binlog file. In this case, we reset the counters to make us not skip + the next event group, and queue an artificial Format Description + event. The previously fetched incomplete event group will then be + rolled back when the Format Description event is executed by the SQL + thread. + + A similar case is if the reconnect somehow connects to a different + master server (like due to a network proxy or IP address takeover). + We detect this case by noticing a change of server_id and in this + case likewise rollback the partially received event group. + */ + Format_description_log_event fdle(4); + + if (mi->prev_master_id != mi->master_id) + sql_print_warning("The server_id of master server changed in the " + "middle of GTID %u-%u-%llu. Assuming a change of " + "master server, so rolling back the previously " + "received partial transaction. Expected: %lu, " + "received: %lu", mi->last_queued_gtid.domain_id, + mi->last_queued_gtid.server_id, + mi->last_queued_gtid.seq_no, + mi->prev_master_id, mi->master_id); + else if (strcmp(rev.new_log_ident, mi->master_log_name) != 0) + sql_print_warning("Unexpected change of master binlog file name in the " + "middle of GTID %u-%u-%llu, assuming that master has " + "crashed and rolling back the transaction. Expected: " + "'%s', received: '%s'", + mi->last_queued_gtid.domain_id, + mi->last_queued_gtid.server_id, + mi->last_queued_gtid.seq_no, + mi->master_log_name, rev.new_log_ident); + + mysql_mutex_lock(log_lock); + if (likely(!fdle.write(rli->relay_log.get_log_file()) && + !rli->relay_log.flush_and_sync(NULL))) + { + rli->relay_log.harvest_bytes_written(&rli->log_space_total); + } + else + { + error= ER_SLAVE_RELAY_LOG_WRITE_FAILURE; + mysql_mutex_unlock(log_lock); + goto err; + } + rli->relay_log.signal_update(); + mysql_mutex_unlock(log_lock); + + mi->gtid_reconnect_event_skip_count= 0; + mi->events_queued_since_last_gtid= 0; + } + mi->prev_master_id= mi->master_id; + if (unlikely(process_io_rotate(mi, &rev))) { error= ER_SLAVE_RELAY_LOG_WRITE_FAILURE; |