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Displaying posts with tag: tuning (reset)
The write cache: Swap insanity tome III

Swapping has always been something bad for MySQL performance but it is even more important for HA systems. It is so important to avoid swapping with HA that NDB cluster basically forbids calling malloc after the startup phase and hence its rather complex configuration.

Probably most readers of this blog know (or should know) about Linux swappiness setting, which basically controls how important is the file cache for Linux. Basically, with InnoDB, since the file cache is not important we add “vm.swappiness = 0″ to “/etc/sysctl.conf” and run “sysctl -p” and we are done.

Swappiness solves part of the swapping issue but not all. With Numa systems, the picture is more complex and swapping can occur because of a memory imbalance between the physical cpus, the sockets and not cores. Jeremy Cole explained this here and …

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Get Even More from MySQL With MySQL Performance Tuning Training

With each release, the MySQL database brings you even better performance. To get the most from your MySQL servers, performance tuning is important. And what better route than to take the MySQL for Performance Tuning training course.

In this four-day instructor-led class you will learn to:

  • Understand the basics of Performance Tuning
  • Use the tools of performance tuning
  • Tune the MySQL server instance to improve performance
  • Improve performance of tables
  • Implement proper Schema Design to improve performance
  • Improve the performance of MySQL queries

This course is available as:

  • Training-on-Demand: Start training within 24 hrs of registering and follow the course at your own pace and from your own desk.
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Optimize MySQL Performance with the Authentic MySQL Training

The MySQL database provides top-level performance. Here are two courses to help you get the most out of your MySQL system.

Troubleshooting MySQL Performance With Sveta Smirnova

This 1 day seminar is an opportunity to interact with Sveta Smirnova, MySQL engineer, expert on MySQL Performance and author of MySQL Troubleshooting.

Sign up for this seminar scheduled for February 28th, 2013 in London, England

Sveta will start from basics, working towards more advanced cases that DBAs would usually need years of experience to identify or …

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Get The Most From MySQL Database With MySQL Performance Tuning Training

Get the most from MySQL Server's top-level performance by improving your understanding of performance tuning techniques.

MySQL Performance Tuning Class

In this 4 day class, you'll learn practical, safe, highly efficient ways to optimize performance for the MySQL Server. You can take this class as:

  • Training-on-Demand: Start training within 24 hours of registering and follow the instructor-led lecture material through streaming video at your own pace. Schedule time lab-time to perform the hands-on exercises at your convenience.
  • Live-Virtual Class: Follow the live instructor led class from your own desk - no travel required. There are already a range of events on the schedule to suit different timezones and with delivery in languages including English and German.
  • In-Class Event: Travel to a training center to follow this class.

For more information on this class, to see the …

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MySQL AutoTuner

After reading a blog post about MySQL Tuning scripts I thought about the possibility of a fully Automatic MySQL Tuner.

This is how it would work:
A daemon which would connect to your database server and then fetch status variables, just like mysqltuner and such. Then the daemon could decide that a parameter would need to be adjusted and then run "SET GLOBAL …" and write a /etc/mysql/autotuner.cf file which should be included in your my.cnf.

It should have a min/max setting for each option and some thresholds.

Why?

  • Not everyone is a DBA
  • It's could better than the default settings is most cases. Luckily many defaults are updated in 5.6.
  • You're not using my-huge.cf, are you?
  • It could help when there are changing workloads
  • It might be sufficient for …
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Optimising Web Servers

I was lucky enough to attend PyCon-AU recently and one talk in particular highlighted the process of web server optimisation.

Graham Dumpleton’s add-in talk Web Server Bottlenecks And Performance Tuning available on YouTube (with the majority of PyCon-AU talks)

The first big note at the beginning is that the majority of the delay in user’s perception of a website is caused by the browser rendering the page. Though not covered in the talk for those that haven’t used the tool YSlow (for Firefox and Chrome) or Google’s Developer Tools (ctrl-alt-I in Chrome), both tools will …

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NOT IN vs. NOT EXISTS vs. LEFT JOIN / IS NULL: MySQL

When you're spoiled with Oracle's fabulous query transformation capabilities and its really well-done cost-based optimiser, then you might forget how difficult SQL query tuning used to be in the "old days" or with those less sophisticated databases. Here's a really nice explanation of the various means of implementing an ANTI-JOIN in MySQL: http://explainextended.com/2009/09/18/not-in-vs-not-exists-vs-left-join-is-null-mysql/

A CTO Must Never Do This…

Read the original article at A CTO Must Never Do This…

A couple years back I was contacted to look at a very strange problem.

The firm ran flash sales. An email goes out at noon, the website traffic explodes for a couple of hours, then settles back down to a trickle.

Of course you might imagine where this is going. During that peak, the MySQL database was brought to its knees. I was asked to do analysis during this peak load, and identify and fix problems. Make it go faster, please!

First day on the job I’m working with a team of outsourced DBAs. I was also working with a sort of swat team chatting on SKYPE, while monitoring the systems closely.

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The relationship between Innodb Log checkpointing and dirty Buffer pool pages

This is a time-honored topic, and there’s no shortage of articles on the topic on this blog. I wanted to write a post trying to condense and clarify those posts, as it has taken me a while to really understand this relationship.

Some basic facts

  • Most of …
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Momentum MTA Performance Tuning Tips

This post is being constantly updated as we find out more useful information on Momentum tuning. Last update: 2012-05-05.

About 2 months ago I’ve joined LivingSocial technical operations team and one of my first tasks there was to figure out a way to make our MTAs perform better and deliver faster. We use a really great product called Momentum MTA (former Ecelerity) and it is really fast, but it is always good to be able to squeeze as much performance as possible so I’ve started looking for a ways to make our system faster.

While working on it I’ve created a set of scripts to integrate Momentum with Graphite for all kinds of crazy stats graphing, those scripts will be opensourced soon, but for now I’ve decided to share a few tips about performance-related changes …

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Showing entries 31 to 40 of 116
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