…calls made to the storage engine to perform the index record read and then to perform …to MySQL 5.5, and this does not make sense to me. Probably its due to a bug in how…to MySQL 5.5 MRR clearly changes the access pattern to sequential, and hence InnoDB is able to do many read_aheads. Another thing to…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
…be used to perform a lookup on table2 are batched together and sent to the storage engine. The storage engine then … RAID5. Also note that the following changes were made on MySQL 5.6 config: optimizer_switch=’…; In-memory workload Now let’s see how effective are the join optimizations when the …
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a… optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take…
Post: How to change innodb_log_file_size safely
July 9, 2011 By 14 Comments
… need to change MySQL’s innodb_log_file_size parameter (see How to calculate a good InnoDB log file size), you can’t just change the parameter in the my.cnf file and restart the server. If you do, InnoDB will refuse to start… means that InnoDB hasn’t started, and MySQL is trying to access a table with the InnoDB storage engine, which is failing, of course.
Post: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
… been implemented outside of MySQL Storage Engine level for MySQL – reading rows in their physical order can be applied to most storage engines, it certainly can be… other storage engines it often could be done simply by changing meta data (it is not implemented in MySQL anyway though). Very interesting to see how…
Post: Power of MySQL Storage Engines
March 5, 2007 By 3 Comments
… changed and different optimizations may change internal code paths dramatically. I know number of projects being interested in special techniques applying to…of MySQL Storage Engine interface, which means it is also has to be implemented through hacks. In any case this is very interesting how it…
Post: Trying Archive Storage Engine
November 12, 2006 By 6 Comments
…to try how much archive storage engine could help me in this case. Original Table: *************************** 1. row *************************** Name: requests_061111 Engine…mysql mysql 19 Nov 12 11:31 requests_061111.ARM -rw-rw—- 1 mysql mysql… on the table changed from 5 min to about 4 minutes…
Post: Troubleshooting MySQL Upgrade Performance Regressions
February 15, 2012 By Leave a Comment
…to understand what has changed and what exactly changed for worse. I am speaking about MySQL upgrade – version change… baseline. Do not change storage engine at the same …to get new version to pick the old plan no matter how you try and you might be forced to change your application by changing how…
Post: Should we give a MySQL Query Cache a second chance ?
April 10, 2011 By 63 Comments
…query syntax may be hard. Query Cache Storage Engines MySQL Query Cache now stores queries in local …not want changing that to have complete invalidation. Having the option to have some updates not to …is available which makes it hard to understand how exactly MySQL Query Cache is working in many…
Post: MongoDB Approach to Availability
April 30, 2010 By 2 Comments
…to MySQL Server but MySQL Cluster, especially in newer versions which implement “sharding”. Same as commit to NDB Storage engine does not normally mean commit to…to stabilize as well as later develop tools around them. How to check if 2 MongoDB nodes are indeed in sync ? How to…
