April 20, 2014

The Doom of Multiple Storage Engines

One of the big “Selling Points” of MySQL is support for Multiple Storage engines, and from the glance view it is indeed great to provide users with same top level SQL interface allowing them to store their data many different way. As nice as it sounds the in theory this benefit comes at very significant […]

Effect of adaptive_flushing

I recently had the chance to witness the effects of innodb_adaptive_flushing on the performance of InnoDB Plugin 1.0.5 in the wild, which Yasufumi wrote about previously here and here. The server in question was Solaris 10 with 8 disk RAID10 and 2 32GB SSDs used for ZIL and L2ARC, 72G RAM and 40G buffer pool. […]

KISS KISS KISS

When I visit customers quite often they tell me about number of creative techniques they heard on the conferences, read on the blogs, forums and Internet articles and they ask me if they should use them. My advice is frequently – do not. It is fun to be creative but creative solutions also means unproven […]

Recovering CREATE TABLE statement from .frm file

So lets say you have .frm file for the table and you need to recover CREATE TABLE statement for this table. In particular when we do Innodb Recovery we often get .frm files and some mess in the Innodb tablespace from which we have to get data from. Of course we could relay on old […]

Using MMM to ALTER huge tables

Few months ago, I wrote about a faster way to do certain table modifications online. It works well when all you want is to remove auto_increment or change ENUM values. When it comes to changes that really require table to be rebuilt – adding/dropping columns or indexes, changing data type, converting data to different character […]

Heikki Tuuri answers to Innodb questions, Part II

I now got answers to the second portions of the questions you asked Heikki. If you have not seen the first part it can be found here. Same as during last time I will provide my comments for some of the answers under PZ and will use HT for original Heikkis answer. Q26: You also […]

Add an option to Fail on Innodb Initialize failure, Please ?

I already wrote about this issue but as I is third team I’m helping customers to resolve this “frm corruption” issue it is the time to return to it again. During MySQL 5.0 release cycle the change was made so now MySQL does not stop if Innodb storage engine failed to initialize but starts properly… […]

SHOW INNODB STATUS walk through

Many people asked me to publish a walk through SHOW INNODB STATUS output, showing what you can learn from SHOW INNODB STATUS output and how to use this info to improve MySQL Performance. To start with basics SHOW INNODB STATUS is command which prints out a lot of internal Innodb performance counters, statistics, information about […]