Tokutek created the iiBench benchmark back in 2008. The point of the benchmark is to measure the performance of indexed insertions over time. It uses an extremely simple schema, one table with a sequential insertion pattern for the primary key along with three integer fields storing random values. The table maintains 3 secondary indexes, each including several of the random integer fields. The iiBench application itself is currently maintained on Launchpad.

B-tree implementations generally require maintenance operations to update leaf nodes (an insertion is one such operation). When the entire B-tree index does not fit in RAM an IO is required, and performance drops dramatically. Fractal Tree Indexes do not exhibit this performance drop as leaf node …

Now that June has arrived it is time to plan what you will do over the summer months. In addition to your summer vacation plans, give thought to MySQL training for you and your team.

Summer is the time to brush up on those critical skills needed to ensure all systems are ready for the holiday shopping season.

In addition to our revised courses, that I talked about in a previous post, we are also running our new Moving to MySQL 5.6 class. This class covers new features in MySQL 5.6, migration planning, and application verification. This class was designed with the experienced MySQL DBA in mind–so it is a fast paced 2-day course.

Percona has a packed summer MySQL training …

I’m interested in meeting up and sharing experiences about using MySQL and managing MySQL servers with people here locally in Madrid. I had a quick look around and could see no MySQL user groups locally, so it might be nice to create such a group and exchange ideas over a beer, coffee or cola every once in a while. If you’re in Madrid and are interested please let me know. I’ve created a temporary  email address: madrid-mysql-users-2013 AT wl0.org (careful with the domain), which you can contact me on to confirm an interest.  Oh and I’d expect these meet ups to be in Spanish, but that’s not a requirement.

Estoy interesado en reunirme y compartir experiencias sobre el uso de MySQL y administración de servidores de MySQL con la gente aquí en Madrid. He echado un vistazo en Internet y no he visto ningún grupo de usuarios de MySQL a nivel local, por lo que sería bueno crear un grupo e intercambiar ideas mientras tomamos …

When looking at high availability for any CMS, and particularly for Drupal, the list of contenders for part or all of the solution is growing and can be daunting. We'll take a look at the various parts of a solution and what options we have.

Go Cloud?

It seems nearly every answer to every problem in IT these days is "The Cloud", but is it?

read more

When looking at high availability for any CMS, and particularly for Drupal, the list of contenders for part or all of the solution is growing and can be daunting. We'll take a look at the various parts of a solution and what options we have.

Go Cloud?

It seems nearly every answer to every problem in IT these days is "The Cloud", but is it?

read more

Engine condition pushdown is a MySQL internal mechanism that is intended to avoid to send non matching rows from the storage engine to the SQL layer. This is very important when the storage engine involves traffic over the network. This mechanism was initially created to optimize MySQL Cluster (NDB) behavior. For the NDB storage engine [...]

One of my coworkers came across a strange quirk in MySQL with default values for not null columns. Take a look at this table:

Create Table Posts
(
     PostID Int Auto_Increment Primary Key
    ,Title Varchar(30) Not Null
    ,Body Text Not Null
    ,Summary Varchar(25) Not Null Default ''
);

Note the column Summary that is marked not null but has a default value of an empty string. Now, try to insert a null value into this column.

Insert Into Posts (Title, Body, Summary) Values ('A title', 'A body', null);

You’ll get this error:

ERROR 1048 (23000): Column 'Summary' cannot be null

Now, using an extended insert (where you specify multiple rows in an insert statement), we can insert the same data and it will complete successfully, although there will be warnings.

Insert Into Posts (Title, Body, Summary) Values ('A title', 'A body', null), ('2nd body', '2nd body', null);

Query OK, 2 rows …

It’s been written about everywhere, but since we keep spotting installations in the wild where people don’t know about it, it probably deserves another mention.

By default, Linux uses the atime option on a disk mount, which means it writes a timestamp (e.g. a write to the drive) every time it reads anything. So in this case, reads cause writes – and also disk seeks, because a read from a file will then trigger having to write to the directory that contains the file. This even occurs if a file is read from the file system’s page cache (reading from the machine’s memory rather than the drive).

Unless you require an audit trail of users reading files, you generally you don’t want this. Thus, you want to add the noatime option to the disk mount in /etc/fstab. If you have just the defaults in there, you just make it defaults,noatime. It’ll doesn’t necesarily require a reboot as you …

In my prior post on the problems with open source, I wrote that one issue that impacts open source revenues is the macro economy, and how a declining or difficult macro economy can result in reduction of revenues to open source companies. The following article talks about how financially troubled Spain is saving a "fortune" by moving to open source. The Spanish government's savings are coming at the expense of proprietary server software companies--most likely Microsoft--but I would be willing to bet that none of this "savings" is flowing to the open source vendors. That is what happens in a difficult macro economy.

In my prior post on the problems with open source, I wrote that one issue that impacts open source revenues is the macro economy, and how a declining or difficult macro economy can result in reduction of revenues to open source companies. The following article talks about how financially troubled Spain is saving a “fortune” by moving to open source. The Spanish government’s savings are coming at the expense of proprietary server software companies–most likely Microsoft–but I would be willing to bet that none of this “savings” is flowing to the open source vendors. That is what happens in a difficult macro economy.

The post Problems with Open …