With MySQL 5.1 reaching release candidate stage, I have been reviewing ALL of the MySQL Certification exam questions to hunt down any items that may now have been superseded by the march of progress. And right now the Merge Storage Engine has caught my eye.

With 5.1 comes the ability to disable the Merge Storage Engine. It used to be that you could not disable the MyIsam, Memory, or Merge engines. They were compiled in and could not be disabled. They were a constant, solid and dependable. But now you can pass --skip-merge to mysqld and disable it.

Does this option effect a lot of people? I honestly don't know. But it will change a few questions on the certification exams. And it may make a great piece of knowledge if they ever publish the Trivial Pursuit MySQL Edition.

On my InfoWorld blog I've posted an interview with Olli Toivainen, Nokia's director of product management.  He's one of the unsung heroes behind the N Series of Linux-based Internet Tablets.  Although I couldn't get him to make any new announcements of future products, he does give quite a bit of good info around the N810 Internet tablet, which I think is one of the coolest devices out there.

For those interested in music, I've also posted an interview with Joe Trohman …

The PHP manual basically tells you not to use Apache 2 with a threaded MPM and PHP as an Apache module. In general, it may be good advice. But, at dealnews.com, we have found it very valuable.

Apache threaded MPMs

Well, first, what is an MPM? It stands for Multi-Processing Module. It is the process model that Apache uses for its children process. Each request that comes in is handed to a child. Apache 1 used only one model for this, the prefork model. That uses one process per Apache child. The most commonly used threaded MPM is the Worker MPM. In this MPM, you have several processes that run multiple threads within it. This is the one I will be talking about. You can read more on Apache MPMs at the …

With the acquisition of MySQL I expect that many people might end up comparing MySQL and PostgreSQL using sysbench. It is like a micro-benchmark utility which includes an oltp mode which is used quite a bit to show MySQL performance. It can actually also be used with PostgreSQL. So this post is about how to configure sysbench to work with PostgreSQL. (Primarily a note for myself since I had to do hunt around to get it configured for PostgreSQL).

 
First download the latest version of sysbench. I had downloaded the version sysbench-0.4.8. After gunzip/untar I had to to figure out few steps to get the right configure script for it.

I am going to use the Sun Studio Compiler (since PostgreSQL in my case is also built with Sun Studio Compiler). So I will need the compiler cc in my …

I've been looking from different angles on ways to make memcached_get() (aka from libmemcached) faster.

I keep toying with different ideas... rewriting it in different ways to see if I can get any performance changes in it.

Thus far... nada... no go.

Yesterday I had the idea of "bypass my write buffer, use writev() to push the data to the client".

This would save me in design two memory copies.

Results?

writev() was slower.

D'oh!

What to do, what to do...

I keep a copy of glibc() on my laptop. I do this for just such the occasion.

How is writev() implemented? It alloc's memory large enough to contain the data, does a copy, and then calls write().

Well crap.

I have never used writev() before, the …

We are hosting a webcast this Wednesday to talk about backing up corporate data to Amazon?s Simple Storage Service (S3) using Amanda Enterprise. We will demonstrate live, how enterprise users can now use Amanda Enterprise to harness Amazon S3 for a complete data backup, archiving and disaster recovery solution. The webcast will take place on Wednesday February 27 at 10:00AM PST and will last about an hour, including a Q&A session at the end. We hope you can join us to discover a new & cost effective way to leverage online storage services such as Amazon S3 as a part of your corporate data protection strategy. Click here to register.

Sun acquires innotek (VirtualBox). The 451 Group publishes report on GPLv3 impact. Alfresco releases open source survey results. (and more)

Sun Microsystems Announces Agreement to Acquire innotek, Expanding Sun xVM Reach to the Developer Desktop, Sun Microsystems (Press Release)

The 451 Group: Latest Version of GPL Software License Causes Disruption in the Enterprise Open Source Industry, The 451 Group (Press Release)

Alfresco?s Open Source Barometer Survey Reveals Ubuntu & Red Hat Pulling Away in Linux-Based Operating System Deployments, Alfresco Software (Press Release)

…

A customer recently asked what the pros and cons are of using the innodb_file_per_table. It's a good question - since the right answer will depend a lot on your data. I'm a fan of the file per table option, it's particularly helpful when you delete a lot of data and want to reclaim the space. So here is the list I came up with:

The pros:
* Normally the InnoDB tablespace never shrinks, but when using file per table you can run run an OPTIMIZE to compact/recreate it (this is a big win).
* You can symlink out individual tables[1] to be on different disk subsystems (can give some improvement, but the global tablespace is still shared).

The cons:
* You can't spread an individual table across several disks (without file per table, it's quite easy to create many segments of a few GB each and move them …

March 2008 will be a month of publicity for CouchDB. I will be giving a total of three presentations around the globe, the northern hemisphere, less then half of that, actually. Anyway.

March 1st, 2008 — Chemnitzer Linux Tage

As early as 9:00 a.m. on a Saturday morning, I’ll be giving the 45 minute version of my Next Generation Data Storage with CouchDB talk to a crowd of hopefully awake Linux enthusiasts. The conference is only 5€ (3€ for students), so be sure to show up! The presentation will be in German and so is the information page.

March 7th, 2008 — O’Reilly ETech — San Diego

This is a big one, and actually, they help sponsoring my flight to the US, so a big thanks upfront! In fact, this is a double session …