I’m setting up my first mysql cluster, and just wanted some clarification on a few things.

In the manual, it says:

Online schema changes. It is not possible to make online schema changes such as those accomplished using ALTER TABLE or CREATE INDEX, as the NDB Cluster engine does not support autodiscovery of such changes. (However, you can import or create a table that uses a different storage engine, and then convert it to NDB using ALTER TABLE tbl_name ENGINE=NDBCLUSTER. In such a case, you must issue a FLUSH TABLES statement to force the cluster to pick up the change.)

MySQL Cluster Exclusive Limitations

However, on another cluster limitations page, it says:

DDL operations. DDL operations (such as CREATE TABLE or ALTER TABLE) are not safe from data node failures. …

I ran into something with mysql cluster today which boggles my mind.  On http://dev.mysql.com/doc/refman/5.0/en/mysql-cluster-config-params-ndbd.html page, it is documented that if we you change datamemory parameter in the config.ini under mysql-cluster like below, you would have to restart nodes to reread the configuration. [NDBD] id=2 HostName=10.0.0.2   # the IP of the first data node DataMemory=6G IndexMemory=512M But when I tried the: [...] …

Microsoft and Kyocera sign patent agreement. Volantis goes open. UnivaUD launches Grid.org community. (and more)

Microsoft and Kyocera Mita Enter Broad Patent Cross-Licensing Agreement, Microsoft / Kyocera Mita (Press Release)

Volantis Removes Price as Barrier for Enterprise Mobile Content Development and Delivery, Volantis (Press Release)

New Open Source Grid and Cluster Community Launches, UnivaUD (Press Release)

Red Hat and Platform Computing Collaborate to Deliver Integrated HPC Solution, Red Hat / Platform Computing …

Lua is a great programming language and I use it as embedded scripting language in

• MySQL Proxy
• wormhole Storage Engine
• lighttpd

What impresses me most it's flexibility. What ever I come up with is only a few lines away ... and I have crazy ideas. Like profiling lua scripts with KCacheGrind.

For profiling lua-scripts you can use

• luaprofiler
• …

Thank you Frankfurt, what an evening! Thanks a lot for the invitation and my trip-sponsors. In fact the people and venue were so nice, I am seriously looking for an excuse to go again.

For housekeeping, here are the promised slides (PDF, 0.662 MB, sans images). In Some Context I wrote:

I rarely see the point of posting the slides of a presentation for people who didn’t see the original presentation. Yet, this is often requested. I don’t have a problem with posting my […] slides […], but they are of little value without context and I do have a problem with posting things of little value, so here’s the context.

And it goes on to comment the slides I used for my CouchDB presentation in Zurich. The new slides are …

MySQL internally has been debating "what are release criteria" internally. This has me thinking about release criteria and what it means in open source.

Right now I am working my way toward stable versions of the Memecache Engine, and libmemcached.

libmemcached is moving forward very rapidly at this point. Releases occur about once a week at the moment, and I've got enough feedback to know that a number of users (more then 10, less then 50) are pulling heavily off the Mercurial download server. Jedi build their own light-sabers, and Jedi pull open source directly from revision control systems.

A few observations on this:
My users are using RSS. This is the first time I have taken a brand new …

Just a quick note to say I’m leaving today for San Francisco to attend Oracle OpenWorld. I’ll be making my presentation on Thursday at 14:30, in Room 304. Look for IOUG: Oracle Database 11g –The Perfection of a Masterpiece (Session ID: S291070). I’ll be posting more about my OOW adventures here, so please stay tuned. I hope [...]

I had a interesting problem from Yahoo! mail team that they were not able to start the 5.1 server at all on couple of their replication setup boxes. They tried 5.1.20 , 21 and 22 and all are behaving in the same way.

After digging into the box, the mysql error log has the following info that it was failed to open event table.

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      071113 10:09:28 [ERROR] Event Scheduler: Failed to open table mysql.event
071113 10:09:28 [ERROR] Event Scheduler: Error while loading FROM disk.
071113 10:09:28 [Note] Event Scheduler: Purging the queue. 0 events
071113 10:09:28 [ERROR] Aborting
 
Creating new mysql …

I just read Colin Baker's article about a European OSS support provider named Credativ. The Credativ website claims: "credativ support covers a large number of open source projects, including: Debian, Ubuntu, SuSE, Red Hat, Xandros, Mandriva, PostgreSQL, MySQL, Kolab -Groupware, eGroupware, Asterisk, Apache, Squid, Postfix, Exim, sendmail, Cyrus, SpamAssassin, ClamAV, Samba, OpenLDAP, Nagios, DRBD, Keepalived, Amanda, XEN, Gnome and KDE, OpenOffice.org, Firefox and many more." They seem to have a very similar business model to OpenLogic. Apparently the news is that Credativ has been successful in Germany for the past two years and is now expanding to the UK. It... READ MORE

So I have been very interested with event-driven publishing and apparently (as I have often discovered) oracle has already beaten me to it by having a whole system in place before I had even thought about it.


What is Event-Driven Publishing?

Well, for short it means that an event triggered the data or content to be published and not like request-driven publishing which is when a user asks to see this data and it is generated per request. The event could be the database being updated with new data, which triggers all the relevant parts of the websites to be updated accordingly. Therefore technically, you save the time that you would have processed this information before hand and it, depends on the situation, can significantly increase speed.

Now I did some more research …