Last Summer I implemented a non-blocking client API in MariaDB, and it was included in the MariaDB 5.5 release. But somehow I never got around to announcing it.

However, that did not prevent Brian White from noticing it, and using it to implement a new mysql binding for node.js called mariasql.

Now, node.js is a single-threaded, event-driven framework for web application sever development. In such frameworks, all I/O is done non-blocking or asynchronously, as are all other actions that may need to wait for external events. There is a single event loop which uses a poll() or similar system call to wait for any pending I/O or other event to complete, and then dispatches the appropriate event handler(s). Such frameworks are often used instead of a multi-threaded …

In a previous post, I had demonstrated how subquery materialization, introduced in MySQL 5.6.5, improves the performance of certain queries, like query Q16 of DBT3. Such improvement was easily explained:

• Subquery materialization has a high start up cost (it needs to create and fill the temporary table).
• But afterwards it has fast lookups (temporary table has a hash index, no duplicates, and is in memory).
• In other words, compared to EXISTS, the first evaluation of the IN predicate is slow (high start up cost) and all following evaluations are fast (just a hash lookup).
• In the DBT 3 setup, one outer table (named "part") has 200,000 rows, so there are 200,000 evaluations of …

Percona is glad to announce the release of Percona Server 5.5.27-29.0 on October 11th, 2012 (Downloads are available here and from the Percona Software Repositories).

Based on MySQL 5.5.27, including all the bug fixes in it, Percona Server 5.5.27-29.0 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details of the release can be found in the 5.5.27-29.0 milestone at Launchpad.

New Features:

• …

If you missed Percona Live MySQL Conference in NYC, download these Continuent Tungsten talks!

FUTURE-PROOFING MYSQL FOR THE WORLD-WIDE DATA REVOLUTION by Robert Hodges SOLVING LARGE-SCALE DATABASE ADMINISTRATION WITH CONTINUENT TUNGSTEN by Robert Hodges and Neil Armitage CONSOLIDATE YOUR SHARDED DATABASE INDEXES IN REAL-TIME by Jeff Mace

We are sponsoring the upcoming Percona Live events in

Mark Leith writes that it’s time to say goodbye to SHOW PROCESSLIST in MySQL 5.6, and use the Performance Schema replacement for it instead, because the older tools cause some blocking, and the Performance Schema replacement is completely non-blocking.

On the face of it that’s a good thing, but I wonder whether we’ll want to keep some blocking functionality around anyway. Inspecting systems that are doing concurrent work can be hard unless you can see a variety of views on them. One such is looking at the state of all the concurrent work at an instant in time. This is sometimes indispensable for troubleshooting: you will see causes and effects you’ll never see in counters and metrics, no matter how many you capture or how sophisticated the analysis.

I haven’t seen MySQL 5.6 in production usage …

Last week, Baron wrote a great post entitled “What’s the benefit of the cloud?” The post was short and made the point that “the benefit of the cloud” is “less ops, more dev.” But Baron is coming from the point of a developer, and from the point of an ops person, there is not necessarily “less ops”.

Some commenters made points along the lines of, “you can just rent rack space in some datacenter for that.” And I agree. There are some ops benefits that Amazon adds, such as easier monitoring and backups, but for the most part, there is not *less* work from an operations standpoint when you are in a cloud environment – my time doing remote DBA work at Pythian and PalominoDB certainly taught me that!

There are still …

Last week, Baron wrote a great post entitled “What’s the benefit of the cloud?” The post was short and made the point that “the benefit of the cloud” is “less ops, more dev.” But Baron is coming from the point of a developer, and from the point of an ops person, there is not necessarily “less ops”.
Some commenters made points along the lines of, “you can just rent rack space in some datacenter for that.” And I agree. There are some ops benefits that Amazon adds, such as easier monitoring and backups, but for the most part, there is not *less* work from an operations standpoint when you are in a cloud environment – my time doing remote DBA work at Pythian and PalominoDB certainly taught me that!
There are still …

MySQL Troubleshooting – What To Do When Queries Don’t Work is a recent publication that you will want to have on your bookshelf. A college professor once lectured to one of my classes that it was easy to teach programming but nearly impossible to teach debugging as there were so many factors involved. The quote the stuck with me was, “Is is very heard to think as dumb as the machine.”

MySQL can prove to be a difficult software beast to keep happy. This book is a guide on everything from simple syntax errors to trouble shooting system environment issues. It is clearly written, concise, and has several tricks & Tips that are invaluable. This is not a cookbook on solving MySQL problems but a guide on how to investigate the various reasons for hanging queries, poor performance, on just puzzling hangs.

So who needs this book? Intermediate to advanced level DBAs or those wishing to to become one.

Sveta Smirnova …

Read the original article at Why do people leave consulting?

As a long time freelancer, it’s a question that’s intrigued me for some time. I do have some theories… First, definitions… I’m not talking about working for a large consulting firm. Although this role may be called “consultant”, my meaning is consultant as sole proprietor, entrepreneur, gun for hire or lone wolf. 1. Make more [...]

For more articles like these go to Sean Hull's Scalable Startups

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Call for Papers for the annual Percona Live MySQL Conference and Expo in Santa Clara, are set to close at the end of the day tomorrow Oct. 12th. Please consider submitting one or more speaking proposals. If you are selected to speak you will receive a free full conference pass valued at over $1,500.

In addition, Super Saver Registration for this conference and Advanced Rate registration for our London conference end tomorrow as well. Sign up now before the price goes up!

Submit your papers and or register here: http://www.percona.com/live/mysql-conference-2013/

or here for London: http://www.percona.com/live/london-2012/