Monthly Archives - August 2015

MySQL Quality Assurance: A Vision for the Future by Roel Van de Paar (Final Episode 13)

MySQL Quality Assurance

Welcome to the final – but most important – episode in the MySQL QA Series.
In it, I present my vision for all MySQL Quality Assurance – for all distributions – worldwide.
Episode 13: A Better Approach to all MySQL Regression, Stress & Feature Testing: Random Coverage Testing & SQL Interleaving
1. pquery Review
2. Random Coverage Testing
3. SQL […]

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Percona Live Amsterdam Discounted Pricing and Community Dinner!

The countdown is on for the annual Percona Live Data Performance Conference and Expo in Europe! This year the conference will be taking place in the great city of Amsterdam September 21-23rd. This three day conference will focus on the latest trends, news and best practices in the MySQL, NoSQL and Data in the Cloud markets, […]

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MySQL replication primer with pt-table-checksum and pt-table-sync

MySQL replication is a process that allows you to easily maintain multiple copies of MySQL data by having them copied automatically from a master to a slave database.
It’s essential to make sure the slave servers have the same set of data as the master to ensure data is consistent within the replication stream. MySQL […]

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MySQL QA Episode 12: My server is crashing… Now what? For customers or users experiencing a crash

My server is crashing… Now what?
This special episode in the MySQL QA Series is for customers or users experiencing a crash.

A crash?

Cheat sheet: https://goo.gl/rrmB9i
Sever install & crash. Note this is as a demonstration: do not action this on a production server!
sudo yum install -y http://www.percona.com/downloads/percona-release/redhat/0.1-3/percona-release-0.1-3.noarch.rpm
sudo yum install -y Percona-Server-client-56 Percona-Server-server-56
sudo service mysql start

Gimme Stacks!

Debug info packages (can […]

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The MySQL query cache: Worst enemy or best friend?

During the last couple of months I have been involved in an unusually high amount of performance audits for e-commerce applications running with Magento. And although the systems were quite different, they also had one thing in common: the MySQL query cache was very useful. That was counter-intuitive for me as I’ve always expected […]

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PXC – Incremental State transfers in detail

IST Basics
State transfers in Galera remain a mystery to most people.  Incremental State transfers (as opposed to full State Snapshot transfers) are used under the following conditions:

The Joiner node reports Galera a valid Galera GTID to the cluster
The Donor node selected contains all the transactions the Joiner needs to catch up to the rest […]

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MySQL QA Episode 11: Valgrind Testing: Pro’s, Con’s, Why and How

MySQL QA Episode 11

Today’s episode is all about Valgrind – from the pro’s to the con’s, from the why to the how! This episode will be of interest to anyone who is or wants to work with Valgrind on a regular or semi-regular basis.

Pro’s/Why
Con’s
How

Using the latest version
sudo [yum/apt-get] install valgrind
#OR#
sudo [yum/apt-get] remove valgrind
sudo [yum/apt-get] install bzip2 glibc*
wget http://valgrind.org/downloads/valgrind-3.10.1.tar.bz2
tar […]

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Percona XtraBackup 2.2.12 is now available

Percona is glad to announce the release of Percona XtraBackup 2.2.12 on August 3, 2015. Downloads are available from our download site or Percona Software Repositories.
Percona XtraBackup enables MySQL backups without blocking user queries, making it ideal for companies with large data sets and mission-critical applications that cannot tolerate long periods of downtime. […]

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Checkpoint strikes back

In my recent benchmarks for MongoDB, we can see that the two engines WiredTiger and TokuMX struggle from periodical drops in throughput, which is clearly related to a checkpoint interval – and therefore I correspond it to a checkpoint activity.
The funny thing is that I thought we solved checkpointing issues in InnoDB once and […]

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