Anybody else noticed that Percona appears to not be a US entity any more?

I observed it today.

$ sudo /usr/bin/innobackupex ...
InnoDB Backup Utility v1.5.1-xtrabackup; Copyright 2003, 2009 Innobase Oy
and Percona Ireland Ltd 2009-2012.  All Rights Reserved.

This software is published under
the GNU GENERAL PUBLIC LICENSE Version 2, June 1991.

In previous versions this did say Percona Inc, 2009-2012.

The footer of the Documentation also states © Copyright Percona Ireland Ltd. 2009-2013.

Introduction

Disk I/O is frequently the performance bottleneck with relational databases. With AWS recently releasing 4,000 PIOPs EBS volumes, I wanted to do some benchmarking with pgbench and PostgreSQL 9.2. Prior to this release the maximum available I/O capacity was 2,000 IOPs per volume. EBS IOPs are read and written in 16Kb chunks with their performance limited by both the I/O capacity of the EBS volumes and the network bandwidth between an EC2 instance and the EBS network. My goal isn't to provide a PostgreSQL tuning guide, an EC2 tuning guide, or a database deathmatch complete with graphs; I'll just be displaying what kind of performance is available out-of-the-box without substantive tuning. In other words, this is an exploratory benchmark not a comparative benchmark. I would have liked to compare the performance of 4,000 PIOPs EBS volumes with 2,000

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Percona published Linkbench results. It looks like they set   [Read more...]

With databases, choices of algorithms influence performance characteristics significantly. It is often very easy to find a situation where one database will perform much worse than others, which is why you will hear database engine developers cry out that benchmarks are flawed.

The best benchmark is one that closely matches what your application actually does, which is why you see the TPC create benchmarks to match hypothetical situations - like a warehouse that has inventory arriving and being shipped out all the time. These situations in turn create “workloads” on the database. To give some context, a workload may behave perform differently on a different database engine because of how many concurrent modifications are required, the ratio of reads/writes, how much data is modified in a transaction, and where in the data set the

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Find duplicates To find duplicate records you can use GROUP BY and count on the attributes which you want to check for duplicates and use HAVING to select all records with a count greater then one: Asume we have the following table and data: CREATE TABLE IF NOT EXISTS test ( column_pk INT(11) NOT NULL [...]

I compared the performance of MySQL 5.6.11 versus 4.0.30 using a read-only workload with sysbench. Performance was much better for 5.6.11 in most cases. At low-concurrency MySQL 4.0 was a bit faster. MySQL 5.6.11 was faster at high-concurrency and when doing many page reads per second. The product has improved a lot since I started using MySQL.

I followed most of my advice on building and configuring MySQL 5.6 for peak performance. I used two test servers - one for the sysbench clients and the other for mysqld. Each server has 16 real cores and 32 with HT enabled. Each test server has 144 GB of memory and fast storage that can do ~150,000 16 KB page reads/second.

The tests selected 1 row by primary key per query and all queries used auto-commit mode.  [Read more...]

This is a long due maintenance release of openark-kit. This release includes bugfixes and some enhancements, mainly to oak-online-alter-table.

oak-online-alter-table Changes / bug fixes include:

• Support for keyword-named columns
• Use of FORCE INDEX due to lack of MySQL's ability for figure out the chunking key at all times
• --sleep-ratio option added; allows for sleep time proportional to execution time (as opposed to constant sleep time with --sleep)
• Support for chunk-retry (in case of deadlock) via --max-lock-retries)
• Fixed order of cleanup
• Fixed bug with verbose messages with non-integer

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This little guide will describe the steps you have to take to use utf-8 in a complete web application using MySQL and PHP. The Database You have to specify the utf8 character set on all tables and text columns in your database. This will ensure that MySQL stores and retrieves the values encoded in UTF-8. [...]

In my previous post, I wrote about when data gets loaded in and out of cache. The goal of caching is to avoid having to perform disk IO, which if we are talking about hard drives, each operation is about 20 million times slower than CPUs or about 100 thousand times slower than memory.

So today I want to cover the subject of when are we required to do IO? But before I get there I first have to describe how IO works on all our modern operating systems.

An Introduction to Buffered IO

When you read or write to a file, by default you are speaking to a layer in between you and your disks called buffered IO. This layer is designed to increase performance and adds important features such as caching. Without going into this in detail, it’s important to

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This is the required post about things I observed during this years MySQL conference.

Things that are awesome:

• The tables in sessions. I think these were here last year. They are still awesome this year.
• The new style power plugs. They solved the problem of people tripping over daisy chained power strips and the strips being accidentally turned off.
• Massive quantities of coffee and real cream.

Things that can be improved:

• Lunch tickets. I overheard the same conversation a dozen times about people not being able to find their lunch tickets or not really knowing about them.
• Make badges reversible. A badge under observation will be facing the wrong way.

Things that just bumped me:

• The music is different this year. Now it makes me feel like a teenager struggling with a breakup.

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MySQL Sandbox has been updated again. The latest version is 3.0.38, which was just released. There were four releases in the space of one week, and this last one is just a polished edition.

Cherry-picking from the Change log:

• Added option --bind_address to complement the effects of --remote_access;
• The script 'enable_gtid' (for MySQL 5.6 +) now is durable. Previously the changes did not survive a restart.
• Now you can install MariaDB with its bizarre version '10.0'
• It also works well with MySQL 5.7. A bug prevented the creation of 'enable_gtid', but it is

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In my ongoing quest to completely understand InnoDB’s data storage, I came across a quite small and inconsequential waste, which is nevertheless fun to write about. I noticed the following block of pages which were allocated very early in the ibdata1 system tablespace but apparently unused (unnecessary lines removed from output):

$ innodb_space -f ibdata1 space-page-type-regions

start       end         count       type                
13          44          32          ALLOCATED           

Background on the doublewrite buffer

Most people using InnoDB have heard of the “doublewrite buffer”—part of InnoDB’s page flushing strategy. The doublewrite buffer is used as a “scratch area” to write (by

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I attended the OpenWest Conference in Orem, Utah, and have to say its one of the best community organised conferences. There were over 840+ people at the conference (with more walk-in’s), representing a greater than 100% growth rate compared to last year’s conference.

I gave a talk about MariaDB, and its safe to say that we’ve got many new features that that it’s getting very hard to go in-depth in a span of an hour.

One of the highlights for me was attending talks. I give so many talks, and spend a lot of time talking to people about MariaDB and MySQL, that I very

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A few days ago I was doing some cleanup on a passive master database using the MySQL client. I didn't want my commands to be replicated so I executed set sql_log_bin=0 in my session.

One of my queries dropped an unused schema that I knew was corrupt, so I wasn't too surprised when the drop database command crashed the MySQL server. After the crash, the server came back up quickly, and my client automatically reconnected, so it was safe to keep running queries right?

Wrong.

When the client reconnected I lost my session state, so sql_log_bin reverted to 1, and any commands I ran from that point forward would be replicated, which I did not want.

This behavior makes sense, and it's documented in the manual:

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Teradata Q1 disappoints. Actian acquires ParAccel. And more.

For 451 Research clients: Acquisitive Actian adds ParAccel to its growing database portfolio bit.ly/YgeY7k

— Matt Aslett (@maslett) April 29, 2013

For 451 Research clients: Tokutek releases TokuDB database storage engine as open source bit.ly/102xsSW

— Matt Aslett (@maslett) May 1, 2013

For 451 Research clients: Codership replicates partnership success with Galera Cluster for MySQL bit.ly/15dI8Hh

— Matt Aslett (@maslett)

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News and views are an integral part of our modern daily life. When it comes to the information-hungry roles such as database professionals, such need becomes more pressing. Log Buffer is one way to keep abreast of news and views from the world of Oracle, SQL Server, and MySQL.

Oracle:

There is a significant update SLOB 2, Kevin Closson informs.

Charles Hooper is grouping Data Sets by Week Number of the Month.

Chris Antognini has shared a script that is used to demo ITL deadlocks.

As

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