… user activity in MySQL has traditionally been challenging. Most data can be obtained from the slow or general log, but this involves… details are clearly explained here. The plugin writes its output in json format, and supports writing it directly to a file, or… audit_json_file=1 audit_json_socket_name=/tmp/audit.sock #audit_json_socket=1 audit_json_log_file=/var/lib/mysql/audit.log audit…
Post: Replication in MySQL 5.6: GTIDs benefits and limitations - Part 1
May 21, 2013 By 8 Comments
… the documentation are not so clear. For instance: Do we …mysql> show slave status\G [...] Slave_IO_Running: No Slave_SQL_Running: Yes [...] The error log…mysql> show slave status\G [...] Auto_Position: 1 -> GTID-based positioning # Slave #2 mysql> show slave status\G [...] Auto_Position: 0 -> File…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
… vCache configuration, I think vCache can be declared the clear winner. Base MySQL & Benchmark Configuration All benchmarks were conducted with the following…_method = O_DIRECT innodb_log_buffer_size = 128M innodb_flush_log_at_trx_commit = 1 innodb_log_file_size = 1G innodb_log_files_in_group = 2…
Post: Percona XtraDB Cluster (PXC): what about GRA_*.log files ?
December 19, 2012 By Leave a Comment
… GRA log file: [root@node2 mysql]# ls GRA_*.log GRA_3_3.log [root@node2 mysql]# file GRA_3_3.log GRA_3_3.log: data [root@node2 mysql]# ls… */ DELIMITER ; # End of log file ROLLBACK /* added by mysqlbinlog */; /*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/; So it’s clear that the problem…
Post: Measuring the amount of writes in InnoDB redo logs
October 8, 2012 By 4 Comments
… the redo log What is not obvious from the documentation is that while Innodb_os_log_written is incremented when the log file is written, the LSN is incremented when the log buffer is written… can be overlapping writes. Not clear? Let’s look at an example when innodb_flush_log_at_trx_commit is set to…
Post: Multiple purge threads in Percona Server 5.1.56 and MySQL 5.6.2
May 3, 2011 By 13 Comments
…were innodb_buffer_pool_size=16G innodb_log_file_size=1900M innodb_flush_log_at_trx_commit=2 innodb_doublewrite=… to penalize further TPS. MySQL 5.6.2 Results Now let’s test MySQL 5.6.2. It …data presented the other way: Here it becomes very clear that there are no significant differences caused by …
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…_safe –defaults-file=/etc/my.cnf –pid-file=/var/run/mysqld/mysqld.pid –log-error=/var/log/mysqld.log mysql 3172 3137 …of innodb_log_file_size. I won’t give you a full rundown over every option in the file. But again…explain the meaning of the output, so it’s clear what I’m showing them. Then, I go …
Post: Recovery deleted ibdata1
August 10, 2012 By 9 Comments
… the InnoDB main table space – ibdata1 – and redo logs – ib_logfile*. MySQL keeps InnoDB files open all the time. The following recovery technique… existence of these files! But after the restart InnoDB will detect that there is neither system table space nor log files, so it… monitoring system checks that InnoDB files ibdata and ib_logfile* do exist Do not restart MySQL until the further recovery strategy is clear
Post: Using Flexviews - part two, change data capture
March 25, 2011 By 26 Comments
…: $ mysql -e ‘select * from flexviews.binlog_consumer_status\G’ -uroot *************************** 1. row *************************** server_id: 999 master_log_file: binary_log.000001 master_log_size:…it should be clear in a moment. Lets create a table, insert some rows, add a change log, delete rows…
Post: Can MySQL temporary tables be made safe for statement-based replication?
May 26, 2008 By 8 Comments
…*************************** Master_Log_File: mysql-bin.000006 Read_Master_Log_Pos: 98 Relay_Log_File: mysql_sandbox20551-relay-bin.000028 Relay_Log_Pos: 235 Relay_Master_Log_File: mysql-… statements went into the binlog individually, there’s clearly an opportunity to break replication here. It looks …
