| Bug #20821 | INSERT DELAYED fails to write some rows to binlog | ||
|---|---|---|---|
| Submitted: | 3 Jul 2006 13:41 | Modified: | 13 Jul 2006 20:09 |
| Reporter: | Guilhem Bichot | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: Replication | Severity: | S3 (Non-critical) |
| Version: | 5.1-bk | OS: | Linux (linux) |
| Assigned to: | Mats Kindahl | CPU Architecture: | Any |
[5 Jul 2006 6:20]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/8732
[5 Jul 2006 14:59]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/8775
[8 Jul 2006 4:15]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/8949
[13 Jul 2006 20:09]
Paul DuBois
Noted in 5.1.12 changelog. For multiple INSERT DELAYED statements executed in a batch thby e the delayed-insert handler thread, not all rows were written to the binary log.
Description: Under concurrency, several INSERT DELAYED queries issued by different threads get groupped and executed as one bunch by the system delayed_insert thread: bool delayed_insert::handle_inserts(void) { <cut> while ((row=rows.get())) { <cut> if (write_record(&thd, table, &info)) { info.error_count++; // Ignore errors thread_safe_increment(delayed_insert_errors,&LOCK_delayed_status); row->log_query = 0; } <cut> } thd.proc_info=0; pthread_mutex_unlock(&mutex); /* After releasing the mutex, to prevent deadlocks. */ if (mysql_bin_log.is_open()) thd.binlog_query(THD::ROW_QUERY_TYPE, query, query_length, FALSE, FALSE); But (see above) we binlog only one query for the bunch. Specific of 5.1. How to repeat: reset master; create database if not exists mysqlslap; use mysqlslap; CREATE TABLE t1 (id int, name varchar(64)); --exec $MYSQL_SLAP --silent --concurrency=5 --iterations=200 --query="INSERT DELAYED INTO t1 VALUES (1, 'This is a test')" --delimiter=";" sleep 5; select count(*) from t1; => the COUNT(*) will say 1000, but if you do: ../client/mysqlbinlog var/log/master-bin.000001 |grep DELAYED | wc -l 645 Another run showed 610. I.e. hundreds of INSERT DELAYED didn't find their way to binlog. Suggested fix: Move back the binlogging inside the while loop?