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Author Archives: Yves Trudeau

Impact of the sort buffer size in MySQL

The parameter sort_buffer_size is one the MySQL parameters that is far from obvious to adjust. It is a per session buffer that is allocated every time it is needed. The problem with the sort buffer …

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High availability for MySQL on Amazon EC2 – Part 5 – The instance monitoring script

This post is the fifth of a series that started here. From the previous posts of this series, we now have an instance restart script that can restart the database node in case of failure …

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High availability for MySQL on Amazon EC2 – Part 4 – The instance restart script

This post is the fourth of a series that started here. From the previous of this series, we now have resources configured but instead of starting MySQL, Pacemaker invokes a script to start (or restart) …

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High availability for MySQL on Amazon EC2 – Part 3 – Configuring the HA resources

This post is the third of a series that started here. From the previous of this series, we now have two working EC2 instances that are EBS based. The first instance is the monitor, usually …

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High availability for MySQL on Amazon EC2 – Part 2 – Setting up the initial instances

This post is the second of a series that started here. The first step to build the HA solution is to create two working instances, configure them to be EBS based and create a security …

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High availability for MySQL on Amazon EC2 – Part 1 – Intro

Like many, I have been seduced by the power and flexibility of Amazon EC2. Being able to launch new instances at will depending on the load, is almost too good to be true. Amazon has …

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Pacemaker, please meet NDB Cluster or using Pacemaker/Heartbeat to start a NDB Cluster

Customers have always asked me to make NDB Cluster starts automatically upon startup of the servers. For the ones who know NDB Cluster, it is tricky to make it starts automatically. I know at least …

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NDB API examples, the trivia to make ndbapi_scan works!

When I did NDB Cluster engagements, it happened a few time that I had to cover the NDB API. Once, a customer asked an example on how to perform a simple scan. Remembering that some …

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Finding your MySQL High-Availability solution – Replication

In the last 2 blog posts about High Availability for MySQL we have introduced definitions and provided a list of ( questions that you need to ask yourself before choosing a HA solution. In this …

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Finding your MySQL High-Availability solution – The questions

After having reviewed the definition my the previous post (The definitions), the next step is to respond to some questions. Do you need MySQL High-Availability? That question is quite obvious but some times, it is …

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