June 20, 2013

Post: read_buffer_size can break your replication

June 6, 2012 By 12 Comments

… going to talk about read_buffer_size and how this …to load the 4 million rows with LOAD DATA INFILE: MasterA (test) > LOAD DATA INFILE ‘/tmp/data’ INTO TABLE t; Query…to check the binary logs of both masters. MasterA: masterA> mysqlbinlog data/mysql-bin.000004 | grep block_len #Begin_load_query…

Filed Under: MySQL

Post: Distributed Set Processing with Shard-Query

May 14, 2011 By 27 Comments

…how to distribute the computation of aggregation queries over time. I realised that I could apply these same mathematical concepts to distributed queries…MySQL storage nodes are supported. Amdahl’s law applies to…CHECK * on the base table…

Filed Under: MySQL

Post: Is MySQL 5.6 slower than MySQL 5.5?

February 18, 2013 By 23 Comments

…to be considered for the query the more time the query optimization is likely to take. I also would expect newer code to…mysql-socket=/tmp/mysql_sandbox5610.sock –mysql-user=msandbox_rw –mysql-password=msandbox –oltp-table-size…

Filed Under: MySQL Tagged With: , , ,

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

March 4, 2013 By 7 Comments

…Checks | 24.224336624145508 | +—–+————————————————————————–+——————–+ OK, now I’m starting to…mysql: SET GLOBAL innodb_ft_server_stopword_table=’test/innodb_ft_list2′; Query OK, 0 rows affected (0.00 sec) mysql…

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

Post: MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark

March 11, 2013 By 7 Comments

…query, see how many pages were read from disk versus how many page requests their were: mysql…tables | 0.000015 | 0.000016 | 0.000000 | 0.000000 | 0 | 0 | 0 | 0 | 0 | 0 | | 3 | checking…

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Post: Heikki Tuuri answers to Innodb questions, Part II

November 4, 2007 By 13 Comments

…size Q36: There have been several MySQL bugs opened about multi-core scalability (concurrent queries…table where id=5 show innodb status: Hash table size…check with Alexander or check myself to…

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Post: Investigating MySQL Replication Latency in Percona XtraDB Cluster

March 3, 2013 By 13 Comments

…to pretty significant load. sysbench –test=oltp –mysql-user=root –mysql-password=”" –oltp-table-size…to DPE1 is blocked for some time. To check this idea I decided to use the sysbench script with very simple point update queries to…

Filed Under: Benchmarks, Insight for DBAs, MySQL, XtraDB Cluster Tagged With: , ,

Post: Recovering Innodb table Corruption

July 4, 2008 By 22 Comments

…to CHECK your MyISAM table you use for recovery after MySQL crashes to make sure indexes are not corrupted. So we looked at how to…

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Post: InnoDB Full-text Search in MySQL 5.6 (part 1)

February 26, 2013 By 1 Comment

…to find out how to make InnoDB FTS blazingly-fast, but simply to get a sense of how it works compared to…mysql> delete from dir_test_innodb LIMIT 200000; Query OK, 200000 rows affected (8.65 sec) mysql> optimize table dir_test_innodb; +———————-+———-+———-+———-+ | Table…

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

Post: Find unused indexes

June 30, 2012 By Leave a Comment

…MySQL we should try another approach. Percona Toolkit has a tool to check the usage of our index from the slow query…size. Conclusion We’ve learnt how to…

Filed Under: Insight for DBAs, Insight for Developers, MySQL, Percona Software
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