InnoDB scalability issues due to tables without primary keys

Each day there is probably work done to improve performance of the InnoDB storage engine and remove bottlenecks and scalability issues. Hence there was another one I wanted to highlight: Scalability issues due to tables without primary keys. This scalability issue is caused by the usage of tables without primary keys. This issue typically shows itself as contention on the InnoDB dict_sys mutex. Now the dict_sys mutex controls access to the data dictionary. This mutex is used at various important

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On SSDs – Lifespans, Health Measurement and RAID

Solid State Drive (SSD) have made it big and have made their way not only in desktop computing but also in mission-critical servers. SSDs have proved to be a break-through in IO performance and leave HDD far far behind in terms of Random IO performance. Random IO is what most of the database administrators would be concerned about as that is 90% of the IO pattern visible on database servers like MySQL. I have found Intel 520-series and Intel 910-series

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Join Optimizations in MySQL 5.6 and MariaDB 5.5

This is the third blog post in the series of blog posts leading up to the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. This blog post is targeted at the join related optimizations introduced in the optimizer. These optimizations are available in both MySQL 5.6 and MariaDB 5.5, and MariaDB 5.5

Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact

I have been working with Peter in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking optimizer enhancements one by one. So in the same way this blog post is aimed at a new optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5

Profiling your slow queries using pt-query-digest and some love from Percona Server

This guide will get you up and running with how to identify the bottleneck queries using the excellent tool pt-query-digest. You will learn how to use and analyze the output returned by pt-query-digest. You will also learn some differences between slow query logging in various MySQL versions. Later on in the post I will also show you how to make use of the extra diagnostic data available with Percona Server.

Understanding B+tree Indexes and how they Impact Performance

Indexes are a very important part of databases and are used frequently to speed up access to particular data item or items. So before working with indexes, it is important to understand how indexes work behind the scene and what is the data structure that is used to store these indexes, because unless you understand the inner working of an index, you will never be able to fully harness its power.

On Covering Indexes and Their Impact on Performance

The purpose of this post is to describe what covering indexes are and how they can be used to improve the performance of queries. People mostly use indexes to filter or sort the results but not much thought is given to actually reduce the disk reads by using proper indexes. So I will show you how to reduce disk reads and hence improve the performance of queries by utilizing indexes properly.

MySQL: Using Views as Performance Improvement Tools

The most basic and most oft-repeated task that a DBA has to accomplish is to look at slow logs and filter out queries that are suboptimal, that consume lots of unnecessary resources and that hence slow down the database server. This post looks at why and how VIEWs can help against such suboptimal operations.

Tuning important Apache parameters.

Although Apache performance can be improved by adding additional hardware resources such as more RAM, faster CPU, but most of the times, the real problem is that the webserver hasn't been configured properly and is not delivering optimal performance. Hence, the reason for this post is to get the important Apache parameters configured properly so as to get the maximum performance out of Apache with existing hardware resources