June 18, 2013

Post: Migrating between MySQL schemas with Percona Xtrabackup

June 10, 2013 By 2 Comments

…MySQL schema and then reload it with a different schema name on…on larger schemas. One of the downsides to mysqldump is the need to scan the full tables and in turn…the redo-logs to ensure that …on the same server.  This will allow you to compare and restore values (potentially corrupted via user error…

Filed Under: Insight for DBAs, MySQL Tagged With: , , ,

Post: Is Synchronous Replication right for your app?

May 14, 2013 By 18 Comments

…on standard MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL… a quorum?  Well, it turns out transaction ordering really, really matters… queue on their nodes will get a deadlock error. So, the…the fsync:  set innodb_flush_log_at_trx_commit to …

Filed Under: MySQL, Percona Software, XtraDB Cluster Tagged With: , , , , , ,

Post: Innodb vs MySQL index counts

November 29, 2011 By 6 Comments

… had a customer recently who a few strange errors in their mysqld.err log: [ERROR] Table database_name/table_name contains 8 indexes… 7 defined in the MySQL This customer was running Percona Server 5.1 and they got this error on two tables during a… for how that turned out, but this basically will regurgitate the entire Innodb Data dictionary to the mysqld error log file. If I…

Filed Under: MySQL

Post: Debugging MySQL SSL problems

November 8, 2012 By Leave a Comment

… and this was already working on an existing environment with the same MySQL version.  I had already added…error log (clean as a whistle!) Trying to find an option for the mysql cli that will output the actual SSL error… setup a simple SSL client and server, which turns out to be a great way to verify…

Filed Under: MySQL

Post: Replication checksums in MySQL 5.6

February 15, 2013 By 3 Comments

…ll now turn on replication checksums on the slave: slave1 [localhost] {msandbox} ((none)) > set global slave_sql_verify_checksum=ON; Query OK…: # mysqlbinlog –verify-binlog-checksum mysql_sandbox18676-relay-bin.000002 [...] ERROR: Error in Log_event::read_log_event(): ‘Event crc check failed! …

Filed Under: MySQL Tagged With: , , ,

Post: InnoDB Full-text Search in MySQL 5.6: Part 2, The Queries!

March 4, 2013 By 7 Comments

…word_length. First, MyISAM, with MySQL 5.5, on the SEO data set: mysql: SELECT id, title, MATCH(title,… here’s what appeared in the server’s error log: InnoDB: invalid column type for stopword table … results aren’t even close to identical. As it turns out, the full record for “Alphonso Lee Peterson…

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: , , , , ,

Post: Impact of logging on MySQL’s performance

February 10, 2009 By 8 Comments

… on CentOS release 4.7 MySQL setting There were two cases considered CPU- and IO-bound. Each case had three options: logging turned off; logging… depend on logging – the difference doesn’t exceed the measurement error. The query rate in this case is about 1000 per second. Logging…

Filed Under: Benchmarks

Post: Be productive with the MySQL command line

December 21, 2012 By 14 Comments

… good size for you InnoDB redo logs: the estimation is based on the variation of the Log Sequence Number during a given period…: mysql> tee queries.log Logging to file ‘queries.log‘ mysql> use sakila Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed mysql> select count(*) from sakila; ERROR 1146 (42S02…

Filed Under: Insight for DBAs, MySQL

Post: MySQL Binaries Percona build10

December 11, 2008 By 12 Comments

…turn on / off query statistics for microslow patch and user statistics in runtime. Next variables were added: | slow_query_log | ON | | slow_query_log…log | 1.1 | Percona | GPL | | | mysqld_safe_syslog.patch | Patch allows redirect output of error.log…

Filed Under: Percona Software Tagged With: ,

Post: Which Linux distribution for a MySQL database server? A specific point of view.

December 8, 2011 By 38 Comments

…very carefully, but it never turned out to be any problem. On the other end there are Debian…’t a month that I log in to a system based on either distribution where there are no…downtime, stopped MySQL and… error – text editor has not been properly installed, so you cannot upgrade MySQL either until…

Filed Under: Insight for DBAs, MySQL
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