Using disk snapshots to perform MariaDB backups has become more and more common, but this seems to have been limited to Linux and Cloud environments. There seems that there has been a notion that Snapshots cannot be done on native Windows, the way we can do snapshots using LVM on Linux for example. This is actually False, if you use the NTFS filesystem snapshoting is built in and has been so for a long time, the base for it is the Volume Snapshot Service (VSS) which was introduced as far back as Windows XP.

Using Snapshots to backup on Linux or Windows works well, assuming that the storage engine you use can recover on startup, the backups created this was are physically consistent but not logically, but InnoDB will recover this. Also note that any warnings about using snapshots with MyISAM also applies to the mysql database, i.e. the database metadata. Usually though, this …

This article discusses about the approach taken by InnoDB Storage Engine of MySQL to provide the repeatable read isolation level.  First, an example is presented to demonstrate the two different designs that are possible.  Then the design used in InnoDB is presented followed by a short discussion about the advantages and disadvantages of this design choice.  As part of this discussion, we also present a performance optimization done in MySQL 5.6. 
An Example Scenario

I used MySQL 5.5 for this purpose.  Let us create the following tables t1 and t2 in the test database that is available by default. Even though the default storage engine in MySQL 5.5 is InnoDB, I explicitly specify it for clarity.  

mysql> use test;
mysql> create table t1 (f1 int) engine=innodb;
mysql> create …

ZFS is a new kind of 128-bit file system that provides simple administration, transactional semantics, end-to-end data integrity, and immense scalability. ZFS is not an incremental improvement to existing technology; it is a fundamentally new approach to data management. ZFS was first introduced in Solaris in 2004 and it is a default filesystem in OpenSolaris, but Linux ports are underway, Apple is shipping it in OS X 10.5 Leopard with limited zfs capability ( Apple shutdown this project afterward due to some known reason), and it will be included in FreeBSD 7.
ZFS Features:

• Pooled Storage Model
• Always consistent on disk
• Protection from data corruption
• Live data scrubbing
…

LVM (Logical Volume Management) is a very important tool to have in the toolkit of a MySQL DBA. It allows you to create and extend logical volumes on the fly. This allows me to, say, add another disk and extend a partition effortlessly. The other very important feature is the ability to take snapshots, that you can then use for backups. All in all its a must have tool. Hence, this guide will allow you to understand various terminologies associated with LVM, together with setting up LVM volumes and in a later part will also show you how to extend...

Isolation is an important part of ACID properties that guarantee that transactions are processed in a reliable manner. But there are four different levels of isolation available and you have to understand each one of them to be able to select the correct one for your needs. This post intends on explaining the four levels together with their effects on locking and performance.

The Problem

Developers often need to have a development database copy of the live production system you are using in able to allow them to test their code and to test new functionality and make schema changes to the database for this new functionality to work.

That’s normal and happens everywhere. A typical DBA task is to make a copy of the live system, sometimes to remove any confidential or sensitive information which perhaps the development database users should not be able to see, and then give them access to this development instance. The developers then “hack away”, changing their code and perhaps things in the database until they are ready to put these new changes into production when they then come along and discuss how to apply these changes into the live systems.

Once the development database has been created it soon becomes stale so often the developers want a new up to date copy …

MySQL backup soon becomes an important matter when the database is used in production. The pain-point comes from the fact that while backuping the database is not available to respond to client requests anymore. With mysqldump - the standard tool for performing MySQL backups - and a large database the operation can go over many tenth of minutes if not hours. If I am running my business on line this is simply not acceptable.

The classical approach to workaround this problem is to take advantage of MySQL replication. I set up a master/slave configuration where the slave acts as copy of the master. Then, when needed, I run mysqldump on the slave without any service interruption on the master.

But ZFS snapshosts bring a new straightforward approach that avoids the pain and the complexity of a master/slave replication.

Snapshots are a key feature of ZFS that allows me to save a copy of …

This tool produces one binary package for each platform where the test runs, and every day there are a few dozen of such packages, waiting to be deleted and replaced by the ones created with the next build.

For long time, several people suggested publishing these binaries for the community. Each time, there was some minor or major impediment, such as getting together different teams and requesting resources from a third one. But the community …

1. Install MySQL::Sandbox

This is a …

This tool produces one binary package for each platform where the test runs, and every day there are a few dozen of such packages, waiting to be deleted and replaced by the ones created with the next build.

For long time, several people suggested publishing these binaries for the community. Each time, there was some minor or major impediment, such as getting together different teams and requesting resources from a third one. But the community …