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SELinux and the MySQL init script

I recently worked with a customer who had a weird issue: when their MySQL server was started (Percona Server 5.5), if they try to run service mysql start a second time, the init script was …

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How to create a rock-solid MySQL database backup & recovery strategy

Have you ever wondered what could happen if your MySQL database goes down? Although it’s evident such a crash will cause downtime – and surely some business impact in terms of revenue – can you …

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Update on the InnoDB double-write buffer and EXT4 transactions

In a post, written a few months ago, I found that using EXT4 transactions with the “data=journal” mount option, improves the write performance significantly, by 55%, without putting data at risk. Many people commented on …

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Generated (Virtual) Columns in MySQL 5.7 (labs)

About 2 weeks ago Oracle published the MySQL 5.7.7-labs-json version which includes a very interesting feature called “Generated columns” (also know as Virtual or Computed columns). MariaDB has a similar feature as well: Virtual (Computed) Columns. The …

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Hyper-threading – how does it double CPU throughput?

The other day a customer asked me to do capacity planning for their web server farm. I was looking at the CPU graph for one of the web servers that had Hyper-threading switched ON and …

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What happens when your application cannot open yet another connection to MySQL

Have you ever experienced a situation where one moment you can connect to the MySQL database and the next moment  you cannot, only to be able to connect again a second later? As you may …

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Do not trust vmstat IOwait numbers

I’ve been running a benchmark today on my old test box with conventional hard drives (no raid with BBU) and noticed something unusual in the CPU utilization statistics being reported. The benchmark was run like …

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Using Apache Hadoop and Impala together with MySQL for data analysis

Apache Hadoop is commonly used for data analysis. It is fast for data loads and scalable. In a previous post I showed how to integrate MySQL with Hadoop. In this post I will show how …

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Database security: Why should you review yours?

Ah database security… the black sheep of topics and something you would really rather not have to deal with right? I mean surely all the fanfare and paranoia is reserved for the neck beards with …

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Percona celebrates its 7th anniversary by giving to open source ecosystem

Today we’re celebrating Percona’s 7th anniversary.  A lot has changed in these past 7 years – we have grown from a two-person outfit focused exclusively on consulting to a 100-person company with teammates in 22 different …

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