The parameter DiskSyncSize is a MySQL Cluster parameter and was added in MySQL 5.1.23.

After the amount of stored bytes of data per file, the data node will fsync (flush) the LCP file to disk, even if a fsync is not needed for consistency.
This is done because the OS will otherwise buffer all the writes, and when a fsync is really needed, it can take a lot of time...

Originally this parameter was hard coded. Now it defaults to 4 Mbyte.

The parameter DiskSyncSize is related to the parameters NoOfDiskPagesToDiskAfterRestartTUP and NoOfDiskPagesToDiskAfterRestartACC which are deprecated right now. It does NOT replace the parameter TimeBetweenLocalCheckpoint.

This parameter should not be changed on any OS (with reasonable settings). With ODIRECT it is not used at all.

Thanks to Jonas for the help.

I've been a little out of touch lately -- crazy accounting project for school -- but was able to carve out a little time to chat with the guys at Engine Yard who are doing some cool things with Ruby. Engine Yard employs Evan Phoenix, the founder of the Rubinius project. The project aims to deliver a virtual machine for Ruby and will be previewing Rails running on Rubinius at RailsConf 2008 later today. According to Evan, Rubinius is an implementation of a Ruby platform, just like the standard Ruby interpreter, IronRuby, MacRuby, JRuby, or countless other implementations. What's interesting... READ MORE

During the webinar "Highly scalable solutions with MySQL and Memcached" Ivan Zoratti announced that Sun will support Memcached as a part of MySQL Enterprise Support.

You may want to check you the white paper "Designing and Implementing Scalable Applications with Memcached and MySQL"

There is another webinar later on today (Designing and Implementing Scalable Applications with Memcached and MySQL), so if you missed out on yesterdays …

We’re looking for experienced OO-PHP programmers. Read all about it here (in Danish only; sorry ’bout that).

As of today, the third, final and largest code release for Open High Availability Cluster has been made available.  This now means that all of the Open HA Cluster code is available as free software.   This will allow developers and admins to access and build complete HA solutions built on source code from the OpenSolaris project.

Right before the launch I grabbed some time with Meenakshi Kaul-Basu, the engineering director at Sun responsible for Availability products, and whose group the Open HA Cluster falls under.  Take a listen to Meenakshi's explanation of the event and her insight:

My interview with Meenakshi (9:29)  …

MySQL Server does not require you to specify name of the index if you're running ALTER TABLE statement - it is optional. Though what might be good practical reasons to specify the key name or omit ?

Things what you should be looking at is how MySQL names indexes automatically as well as what maintaining the indexes.

Lets first speak about naming. If you do not specify index name MySQL will name index by the first column of index created, if there is such index already it will add numeric suffix to it, for example:

PLAIN TEXT SQL:

1. mysql> CREATE TABLE t1(i int, j int);
2. Query OK, 0 rows affected (0.01 sec)
3.  
4. mysql> ALTER TABLE t1 ADD KEY(i,j);
5. Query OK, 0 rows affected (0.03 sec)
6. Records: 0  Duplicates: 0  Warnings: 0
7.  
8. mysql> ALTER TABLE t1 ADD KEY(i);
…

Spinn3r is hiring for an experienced Senior Systems Administrator with solid Linux and MySQL skills and a passion for building scalable and high performance infrastructure.

About Spinn3r:

Spinn3r is a licensed weblog crawler used by search engines, weblog analytic companies, and generally anyone who needs access to high quality weblog data.

We crawl the entire blogosphere in realtime, remove spam, rank, and classifying blogs, and provide this information to our customers.

Spinn3r is rare in the startup world in that we’re actually profitable. We’ve proven our business model which gives us a significant advantage in future product design and expanding our current customer base and feature set.

We’ve also been smart and haven’t raised a dime of external VC funding which gives us a lot …

So, Ray Ozzie has gone on the record to suggest that open source could be a bigger threat to Microsoft than Google is. Savio isn't buying that line, and I'm not sure that I do, either.

Let's be clear about what Ozzie actually said:

...[O]pen source [i]s much more potentially disruptive [than Google].

Open source has disruptive potential. Google is disruptive now. Google is making money now in markets that Microsoft covets, while open source is not cutting into a single Microsoft revenue stream. Not one. Red Hat and Novell's SUSE are almost entirely eating away at the Unix market, while MySQL is creating new markets with web properties. Open source? It doesn't (today) make a dent in Office, Windows, XBox, Dynamics, etc.

So why is …

Quick 'n' Easy LAMP Server For CentOS/RHEL

This tutorial shows a quick way of installing a LAMP server (Linux + Apache + MySQL + PHP/Perl together commonly known as LAMP Server.) on CentOS and RHEL server systems.