In my previous post I was a bit wrong giving Innodb some properties it does not have.
In fact Innodb does not currently sort pages in their position order flushing them to disk. Pages to be flushed are instead identified by other means - LRU and pages which contain oldest LSN (so which were flushed longest time ago).

As pages are to be flushed are identified Innodb looks at pages pages N-1 and N+1 and if they are dirty schedules flush for these as well. Such approach allows to merge few pages together and perform flushes in larger blocks.

It is really interesting to see how much sorting would speed things up, ie how much flushing pages 1 10000 200 20000 300 30000 in order 1, 200, 300, 10000, 20000, 30000 will help compared to random order and if it is worth to bother or if optimization Innodb performs is good enough and IO subsystem and RAID can do the rest.

So I need to create a portal site, where we will require multiple frontends. As most portal's we need to store some state information inside a session. We also need to show how many users are online, but more importantly be able to filter searches in the member database by who is online (we do not need to filter by how long the last site interaction as been, but you never know with changing requirements).

Now in order to filter by users in the member search, we need to have some information about active sessions by user id inside MySQL database. But if we were to put the entire session data inside the database we would have to hit the master on every request to update the session timeout. More importantly we would have to deal with replication lag.

The alternative approach to working around replication lag is using memcache. But with memcache we would not have access to who is currently online in an easy queryable way when we are …

And again we're on our mission to keep XAMPP up-to-date and put the first beta version of the upcoming XAMPP release in our public beta download area.

In this beta we updated: PHP 5 (to 5.2.3), MySQL (to 5.0.45), and phpMyAdmin (to 2.10.2).

Get the downloads at XAMPP BETA.

XAMPP beta versions are always for testing purposes only. There will be no upgrade packages from and to beta versions. To all testers: Many thanks in advance!!

A few weeks back, I posted a couple of blog entries on my recent trip to China. We have seen huge MySQL download numbers from Brazil, Russia, India, China (or "BRIC") with very significant growth in the last few years in China. I tried reading a book by Robert Buderi called "Guanxi (The Art of Relationships) - Microsoft, China and Bill Gates's Plan to Win the Road Ahead" on the development of Microsoft's research lab in China. However, the title should have been a warning to me. As much as I wanted to dive into this book it was just... READ MORE

OK, so we're going to get pretty down-and-dirty in the C source code that handles concurrent inserts... you've been warned. For background on the MyISAM concurrent insert functionality, see my previous article. Before I get going, I'd like to give a big shout out and thank you to Ingo Strüwing and Sergei Golubchik, whose comments and insight on the MySQL internals mailing list helped me keep from exploding while digging through the source code. Ingo and Serg are great resources that any developer looking to better understand the MySQL sources should be grateful to have around.

The way I approached delving into the concurrent insert functionality was actually quite different from the way I looked at the overall MySQL server architecture in Pro MySQL. When writing the book, I relied heavily on the …

And again we're on our mission to keep XAMPP up-to-date and put the first beta version of the upcoming XAMPP release in our public beta download area.

In this beta we updated: PHP 5 (to 5.2.3), MySQL (to 5.0.45), and phpMyAdmin (to 2.10.2).

Get the downloads at XAMPP BETA.

XAMPP beta versions are always for testing purposes only. There will be no upgrade packages from and to beta versions. To all testers: Many thanks in advance!!

Many businesses are now interested in implementing MySQL Cluster as a general high availability solution for their existing databases. This is certainly not a good approach and will often fail due to the limitations currently in the MySQL Cluster implementation (particularly 5.0) and the type of data within the business. However, many are still seeing MySQL Cluster as a magical solution to take out their potential downtime instead of other standard measures such as DRBD, multimaster or scale-out replication.

read more

Many businesses are now interested in implementing MySQL Cluster as a general high availability solution for their existing databases. This is certainly not a good approach and will often fail due to the limitations currently in the MySQL Cluster implementation (particularly 5.0) and the type of data within the business. However, many are still seeing MySQL Cluster as a magical solution to take out their potential downtime instead of other standard measures such as DRBD, multimaster or scale-out replication.

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So, we are not officially looking for PHP/MySQL developers.  However, we could start at any moment.  So, I want to be ready.  There is a really good chance that we will hire someone by the end of the year if not sooner.

So, if you want to work with an up and coming company that uses PHP, MySQL, Gentoo Linux and other open source technology, you can go ahead and send us a resume.  Just email it to me at brianm@dealnews.com.  You will have to confirm your emails.  Spam on that account reach huge numbers years ago, so I am not going to bother with cute notation for my email address.

This job would most likely require moving to Huntsville, AL.  Before you make an Alabama joke, Huntsville has been recognized as a great place for business and technology.  In 2006 it was …

Matt asks (almost as an aside to a post on a related topic): My question: why not just buy Red Hat? Before Red Hat buys MySQL, and gives those database numbers a run for their money? Then, Larry Dingnan writes: A Credit Suisse analyst thinks BEA Systems is likely to go on the auction block in the next three to six months. And the potential buyer is two likely suspects: Private equity firms or Oracle, which indicated it has no plans to slow down its acquisition pace. I'll play Nostradamus and predict that Oracle will not buy Red Hat. Oracle... READ MORE